Staňurová, Jana A novel screening assay for insulin receptor Journal Article In: 2025. @article{noKey,
title = {A novel screening assay for insulin receptor},
author = {Staňurová, Jana},
url = {https://www.biorxiv.org/content/10.1101/2025.03.20.644157v1.abstract},
doi = {https://doi.org/10.1101/2025.03.20.644157},
year = {2025},
date = {2025-03-20},
abstract = {Insulin is a key hormone in glucose homeostasis. Its lack causes severe health complications and has to be compensated by regular administration of insulin. Despite intense long-lasting research, a more stable substitute has yet to be discovered to alleviate patients' issues. Here we report the development of a novel assay for screening potential insulin analogues based on the recently published method DIANA. Our assay meets the need for a fast, non-radioactive method as a sensitive alternative to the commonly used radioactive immunoassay.},
keywords = {MANTIS},
pubstate = {published},
tppubtype = {article}
}
Insulin is a key hormone in glucose homeostasis. Its lack causes severe health complications and has to be compensated by regular administration of insulin. Despite intense long-lasting research, a more stable substitute has yet to be discovered to alleviate patients' issues. Here we report the development of a novel assay for screening potential insulin analogues based on the recently published method DIANA. Our assay meets the need for a fast, non-radioactive method as a sensitive alternative to the commonly used radioactive immunoassay. |
Escós, Alejandra Disrupted α-ketoglutarate homeostasis trains monocyte-derived macrophages towards M2-like phenotype in long-term treated HIV-infection Journal Article In: 2025. @article{noKey,
title = {Disrupted α-ketoglutarate homeostasis trains monocyte-derived macrophages towards M2-like phenotype in long-term treated HIV-infection},
author = {Escós, Alejandra},
url = {https://www.biorxiv.org/content/10.1101/2025.01.15.633214v1.full},
doi = {https://doi.org/10.1101/2025.01.15.633214},
year = {2025},
date = {2025-03-19},
abstract = {Cells of the myeloid lineage, particularly monocytes and macrophages, play a key role in HIV infection by contributing to viral replication, immune response, and maintaining immune balance during suppressive therapy. We hypothesized that metabolic reprogramming and altered chemokine signaling in people living with HIV (PWH) on long-term antiretroviral therapy (ART) affect monocyte transport and polarization due to ongoing inflammation. Therefore, the present study aimed to identify the mechanism of impaired monocyte/macrophage function in PWH on well-treated ART that can lead to clinical intervention strategies to improve health. Single-cell RNA sequencing, immune-phenotyping, and metabolic modeling identified altered expression of chemokine and metabolite receptors and altered metabolic flux in PWH monocytes that decreased monocyte migration. The plasma secretome revealed a nonclassical inflammatory microenvironment in PWH. Integrative multi-omics and single-cell proteomics of differentiated monocyte-derived macrophages (MDMs) detected metabolic reprogramming orchestrated by α-ketoglutarate (AKG) that affected macrophage function and HIV infection. Increased levels of AKG in plasma were shown to occur in PWH under ART. Therefore, when differentiating MDM with serum from PWH or AKG, macrophage function was found polarized towards an M2-like state. AKG alone was shown to increase CCR5 levels and increase HIV-1 infection in MDM. Here, we utilize systems biology-driven identification and ex vivo assays to show impaired macrophage polarization, due to metabolic training, can leads to a low-grade nonclassical inflammatory environment in well-treated PWH.},
keywords = {MANTIS},
pubstate = {published},
tppubtype = {article}
}
Cells of the myeloid lineage, particularly monocytes and macrophages, play a key role in HIV infection by contributing to viral replication, immune response, and maintaining immune balance during suppressive therapy. We hypothesized that metabolic reprogramming and altered chemokine signaling in people living with HIV (PWH) on long-term antiretroviral therapy (ART) affect monocyte transport and polarization due to ongoing inflammation. Therefore, the present study aimed to identify the mechanism of impaired monocyte/macrophage function in PWH on well-treated ART that can lead to clinical intervention strategies to improve health. Single-cell RNA sequencing, immune-phenotyping, and metabolic modeling identified altered expression of chemokine and metabolite receptors and altered metabolic flux in PWH monocytes that decreased monocyte migration. The plasma secretome revealed a nonclassical inflammatory microenvironment in PWH. Integrative multi-omics and single-cell proteomics of differentiated monocyte-derived macrophages (MDMs) detected metabolic reprogramming orchestrated by α-ketoglutarate (AKG) that affected macrophage function and HIV infection. Increased levels of AKG in plasma were shown to occur in PWH under ART. Therefore, when differentiating MDM with serum from PWH or AKG, macrophage function was found polarized towards an M2-like state. AKG alone was shown to increase CCR5 levels and increase HIV-1 infection in MDM. Here, we utilize systems biology-driven identification and ex vivo assays to show impaired macrophage polarization, due to metabolic training, can leads to a low-grade nonclassical inflammatory environment in well-treated PWH. |
Makhmut, Anuar Deep spatial proteomics of ovarian cancer precursor lesions delineates early disease changes and cell-of-origin signatures Journal Article In: 2025. @article{noKey,
title = {Deep spatial proteomics of ovarian cancer precursor lesions delineates early disease changes and cell-of-origin signatures},
author = {Makhmut, Anuar},
url = {https://www.biorxiv.org/content/10.1101/2025.03.19.643504v1},
doi = {https://doi.org/10.1101/2025.03.19.643504},
year = {2025},
date = {2025-03-19},
abstract = {High-grade serous ovarian cancer (HGSOC) is a devastating disease that is frequently detected at an advanced and incurable stage. Advances in ultrasensitive mass spectrometry-based spatial proteomics have provided a unique opportunity to uncover early molecular events in tumorigenesis and common dysregulated pathways with high therapeutic potential. Here, we present a comprehensive proteomic analysis of serous tubal intraepithelial carcinoma (STIC), the HGSOC precursor lesion, covering more than 10,000 proteins from ultralow input archival tissue. We discovered that STICs and concurrent invasive carcinomas were indistinguishable at the global proteome level, revealing a similar level of phenotypic and molecular heterogeneity. Using cell-type resolved tissue proteomics, we revealed strong cell-of-origin signatures preserved in STICs and invasive tumors and identified early dysregulated pathways of therapeutic relevance. These include proliferation and DNA damage repair signatures, as well as onco-metabolic changes, such as increased cholesterol biosynthesis. Finally, we uncovered substantial remodeling of the co-evolving tumor microenvironment, affecting approximately one-third of the stromal proteome, and derived a common signature associated with progressive immunosuppression and ECM restructuring. In summary, our study highlights the power of spatially resolved quantitative proteomics to dissect the molecular underpinnings of early carcinogenesis and provides a rich proteomic resource for future biomarker and drug target discovery.},
keywords = {MANTIS},
pubstate = {published},
tppubtype = {article}
}
High-grade serous ovarian cancer (HGSOC) is a devastating disease that is frequently detected at an advanced and incurable stage. Advances in ultrasensitive mass spectrometry-based spatial proteomics have provided a unique opportunity to uncover early molecular events in tumorigenesis and common dysregulated pathways with high therapeutic potential. Here, we present a comprehensive proteomic analysis of serous tubal intraepithelial carcinoma (STIC), the HGSOC precursor lesion, covering more than 10,000 proteins from ultralow input archival tissue. We discovered that STICs and concurrent invasive carcinomas were indistinguishable at the global proteome level, revealing a similar level of phenotypic and molecular heterogeneity. Using cell-type resolved tissue proteomics, we revealed strong cell-of-origin signatures preserved in STICs and invasive tumors and identified early dysregulated pathways of therapeutic relevance. These include proliferation and DNA damage repair signatures, as well as onco-metabolic changes, such as increased cholesterol biosynthesis. Finally, we uncovered substantial remodeling of the co-evolving tumor microenvironment, affecting approximately one-third of the stromal proteome, and derived a common signature associated with progressive immunosuppression and ECM restructuring. In summary, our study highlights the power of spatially resolved quantitative proteomics to dissect the molecular underpinnings of early carcinogenesis and provides a rich proteomic resource for future biomarker and drug target discovery. |
Douglas, James J. The Implementation and Impact of Chemical High-Throughput Experimentation at AstraZeneca Journal Article In: 2025. @article{noKey,
title = {The Implementation and Impact of Chemical High-Throughput Experimentation at AstraZeneca},
author = {Douglas, James J.},
url = {https://pubs.acs.org/doi/10.1021/acscatal.4c07969},
doi = {https://doi.org/10.1021/acscatal.4c07969},
year = {2025},
date = {2025-03-13},
abstract = {High-throughput experimentation (HTE) is a critical tool in modern pharmaceutical discovery and development. The ability to perform multiple parallel experiments in miniaturized plate-based formats has revolutionized how chemical reactions are optimized. HTE has been especially enabling for catalytic reactions, where the complexity of factors influencing the outcome makes the HTE approach especially suitable. We detail AstraZeneca’s 20-year journey with HTE, from early beginnings to a global community of HTE specialists that are critical to the delivery of our complex portfolio with reduced environmental impact. With an emphasis on catalytic reactions, we provide relevant case study examples from across discovery and development, discuss current technology, data science and workflows, and provide insights into where we see future advances in HTE.},
keywords = {FAST},
pubstate = {published},
tppubtype = {article}
}
High-throughput experimentation (HTE) is a critical tool in modern pharmaceutical discovery and development. The ability to perform multiple parallel experiments in miniaturized plate-based formats has revolutionized how chemical reactions are optimized. HTE has been especially enabling for catalytic reactions, where the complexity of factors influencing the outcome makes the HTE approach especially suitable. We detail AstraZeneca’s 20-year journey with HTE, from early beginnings to a global community of HTE specialists that are critical to the delivery of our complex portfolio with reduced environmental impact. With an emphasis on catalytic reactions, we provide relevant case study examples from across discovery and development, discuss current technology, data science and workflows, and provide insights into where we see future advances in HTE. |
Møller, Tenna A. ActinoMation: a literate programming approach for medium-throughput robotic conjugation of Streptomyces spp. Journal Article In: 2025. @article{noKey,
title = {ActinoMation: a literate programming approach for medium-throughput robotic conjugation of Streptomyces spp.},
author = {Møller, Tenna A.},
url = {https://www.sciencedirect.com/science/article/pii/S2405805X25000389},
doi = {https://doi.org/10.1016/j.synbio.2025.03.005},
year = {2025},
date = {2025-03-11},
abstract = {The genus Streptomyces are valuable producers of antibiotics and other pharmaceutically important bioactive compounds. Advances in molecular engineering tools, such as CRISPR, have provided some access to the metabolic potential of Streptomyces, but efficient genetic engineering of strains is hindered by laborious and slow manual transformation protocols. In this paper, we present a semi-automated medium-throughput workflow for the introduction of recombinant DNA into Streptomyces spp. using the affordable and open-sourced Opentrons (OT-2) robotics platform. To increase the accessibility of the workflow we provide an open-source protocol-creator, ActinoMation. ActinoMation is a literate programming environment using Python in Jupyter Notebook. We validated the method by transforming Streptomyces coelicolor (M1152 and M1146), S. albidoflavus (J1047), and S. venezuelae (DSM40230) with the plasmids pSETGUS and pIJ12551. We demonstrate conjugation efficiencies of 3.33*10-3/0.33% for M1152 with pSETGUS and pIJ12551; 2.96*10-3/0.29%for M1146 with pSETGUS and pIJ12551; 1.21*10-5/0.0012% for J1047 with pSETGUS and 4.70*10-4/0.047% with pIJ12551, and 4.97*10-2/4.97% for DSM40230 with pSETGUS and 6.13*10-2 /6.13% with pIJ12551 with a false positive rate between 8.33% and 54.54%. Automation of the conjugation workflow facilitates a streamlined workflow on a larger scale without any evident loss of conjugation efficiency.},
keywords = {MANTIS},
pubstate = {published},
tppubtype = {article}
}
The genus Streptomyces are valuable producers of antibiotics and other pharmaceutically important bioactive compounds. Advances in molecular engineering tools, such as CRISPR, have provided some access to the metabolic potential of Streptomyces, but efficient genetic engineering of strains is hindered by laborious and slow manual transformation protocols. In this paper, we present a semi-automated medium-throughput workflow for the introduction of recombinant DNA into Streptomyces spp. using the affordable and open-sourced Opentrons (OT-2) robotics platform. To increase the accessibility of the workflow we provide an open-source protocol-creator, ActinoMation. ActinoMation is a literate programming environment using Python in Jupyter Notebook. We validated the method by transforming Streptomyces coelicolor (M1152 and M1146), S. albidoflavus (J1047), and S. venezuelae (DSM40230) with the plasmids pSETGUS and pIJ12551. We demonstrate conjugation efficiencies of 3.33*10-3/0.33% for M1152 with pSETGUS and pIJ12551; 2.96*10-3/0.29%for M1146 with pSETGUS and pIJ12551; 1.21*10-5/0.0012% for J1047 with pSETGUS and 4.70*10-4/0.047% with pIJ12551, and 4.97*10-2/4.97% for DSM40230 with pSETGUS and 6.13*10-2 /6.13% with pIJ12551 with a false positive rate between 8.33% and 54.54%. Automation of the conjugation workflow facilitates a streamlined workflow on a larger scale without any evident loss of conjugation efficiency. |
Jeevannavar, Aditya Cellular heterogeneity in metabolism and associated microbiome of a non-model phytoflagellate Journal Article In: 2025. @article{noKey,
title = {Cellular heterogeneity in metabolism and associated microbiome of a non-model phytoflagellate},
author = {Jeevannavar, Aditya},
url = {https://academic.oup.com/ismej/advance-article/doi/10.1093/ismejo/wraf046/8064733},
doi = {https://doi.org/10.1093/ismejo/wraf046},
year = {2025},
date = {2025-03-09},
abstract = {Single-cell transcriptomics is a key tool for unravelling metabolism and tissue diversity in model organisms. Its potential for elucidating the ecological roles of microeukaryotes, especially non-model ones, remains largely unexplored. This study employed the Smart-seq2 protocol on Ochromonas triangulata, a microeukaryote lacking a reference genome, showcasing how transcriptional states align with two distinct growth phases: a fast-growing phase and a slow-growing phase. Besides the two expected expression clusters, each corresponding to either growth phase, a third transcriptional state was identified across both growth phases. Metabolic mapping revealed a boost of photosynthetic activity in the fast growth over the slow growth stage, as well as down-regulation trend in pathways associated with ribosome functioning, CO2 fixation, and carbohydrate catabolism characteristic of the third transcriptional state. In addition, carry-over rRNA reads recapitulated the taxonomic identity of the target while revealing distinct bacterial communities, in co-culture with the eukaryote, each associated with distinct transcriptional states. This study underscores single-cell transcriptomics as a powerful tool for characterizing metabolic states in microeukaryotes without a reference genome, offering insights into unknown physiological states and individual-level interactions with different bacterial taxa. This approach holds broad applicability to describe the ecological roles of environmental microeukaryotes, culture-free and reference-free, surpassing alternative methods like metagenomics or metatranscriptomics.},
keywords = {MANTIS},
pubstate = {published},
tppubtype = {article}
}
Single-cell transcriptomics is a key tool for unravelling metabolism and tissue diversity in model organisms. Its potential for elucidating the ecological roles of microeukaryotes, especially non-model ones, remains largely unexplored. This study employed the Smart-seq2 protocol on Ochromonas triangulata, a microeukaryote lacking a reference genome, showcasing how transcriptional states align with two distinct growth phases: a fast-growing phase and a slow-growing phase. Besides the two expected expression clusters, each corresponding to either growth phase, a third transcriptional state was identified across both growth phases. Metabolic mapping revealed a boost of photosynthetic activity in the fast growth over the slow growth stage, as well as down-regulation trend in pathways associated with ribosome functioning, CO2 fixation, and carbohydrate catabolism characteristic of the third transcriptional state. In addition, carry-over rRNA reads recapitulated the taxonomic identity of the target while revealing distinct bacterial communities, in co-culture with the eukaryote, each associated with distinct transcriptional states. This study underscores single-cell transcriptomics as a powerful tool for characterizing metabolic states in microeukaryotes without a reference genome, offering insights into unknown physiological states and individual-level interactions with different bacterial taxa. This approach holds broad applicability to describe the ecological roles of environmental microeukaryotes, culture-free and reference-free, surpassing alternative methods like metagenomics or metatranscriptomics. |
Kanappe, Grant A. Heterovalent Click Reactions on DNA Origami Journal Article In: 2025. @article{noKey,
title = {Heterovalent Click Reactions on DNA Origami},
author = {Kanappe, Grant A.},
url = {https://pubs.acs.org/doi/10.1021/acs.bioconjchem.4c00552},
doi = {https://doi.org/10.1021/acs.bioconjchem.4c00552},
year = {2025},
date = {2025-03-05},
abstract = {Nucleic acid nanoparticles (NANPs) fabricated by using the DNA origami method have broad utility in materials science and bioengineering. Their site-specific, heterovalent functionalization with secondary molecules such as proteins or fluorophores is a unique feature of this technology that drives its utility. Currently, however, there are few chemistries that enable fast, efficient covalent functionalization of NANPs with a broad conjugate scope and heterovalency. To address this need, we introduce synthetic methods to access inverse electron-demand Diels–Alder chemistry on NANPs. We demonstrate a broad conjugate scope, characterize application-relevant kinetics, and integrate this new chemistry with strain-promoted azide–alkyne cycloaddition chemistry to enable heterovalent click reactions on NANPs. We applied these chemistries to formulate a prototypical chemical countermeasure against chemical nerve agents. We envision this additional chemistry finding broad utility in the synthetic toolkit accessible to the nucleic acid nanotechnology community.},
keywords = {FLO},
pubstate = {published},
tppubtype = {article}
}
Nucleic acid nanoparticles (NANPs) fabricated by using the DNA origami method have broad utility in materials science and bioengineering. Their site-specific, heterovalent functionalization with secondary molecules such as proteins or fluorophores is a unique feature of this technology that drives its utility. Currently, however, there are few chemistries that enable fast, efficient covalent functionalization of NANPs with a broad conjugate scope and heterovalency. To address this need, we introduce synthetic methods to access inverse electron-demand Diels–Alder chemistry on NANPs. We demonstrate a broad conjugate scope, characterize application-relevant kinetics, and integrate this new chemistry with strain-promoted azide–alkyne cycloaddition chemistry to enable heterovalent click reactions on NANPs. We applied these chemistries to formulate a prototypical chemical countermeasure against chemical nerve agents. We envision this additional chemistry finding broad utility in the synthetic toolkit accessible to the nucleic acid nanotechnology community. |
Alaviuhkola, Juho Discovery of inhibitors for bacterial Arr enzymes ADP-ribosylating and inactivating rifamycin antibiotics Journal Article In: 2025. @article{noKey,
title = {Discovery of inhibitors for bacterial Arr enzymes ADP-ribosylating and inactivating rifamycin antibiotics},
author = {Alaviuhkola, Juho},
url = {https://www.biorxiv.org/content/10.1101/2025.02.20.639278v1.full},
doi = {https://doi.org/10.1101/2025.02.20.639278},
year = {2025},
date = {2025-02-22},
abstract = {ADP-ribosylation is an enzymatic process where an ADP-ribose moiety is transferred from NAD+ to an acceptor molecule. While ADP-ribosylation is well-established as a post-translational modification of proteins, rifamycin antibiotics are its only known small-molecule targets. ADP-ribosylation of rifampicin was first identified in Mycolicibacterium smegmatis, whose Arr enzyme transfers the ADP-ribose moiety to the 23-hydroxy group of rifampicin preventing its interaction with the bacterial RNA polymerase thereby inactivating the antibiotic. Arr homologues are widely spread among bacterial species and present in several pathogenic species often associated with mobile genetic elements. Inhibition of Arr enzymes offers a promising strategy to overcome ADP-ribosylation mediated rifamycin resistance. We developed a high-throughput activity assay, which was applied to screen an in-house library of human ADP-ribosyltransferase-targeted compounds. We identified 15 inhibitors with IC50 values below 5 µM against four Arr enzymes from M. smegmatis, Pseudomonas aeruginosa, Stenotrophomonas maltophilia and Mycobacteroides abscessus. The observed overall selectivity of the hit compounds over the other homologues indicated structural differences between the proteins. We crystallized M. smegmatis and P. aeruginosa Arr enzymes, the former in complex with its most potent hit compound with an IC50 value of 1.3 µM. We observed structural differences in the NAD+ binding pockets of the two Arr homologues explaining the selectivity. Although the Arr inhibitors did not sensitize M. smegmatis to rifampicin in a growth inhibition assay, the structural information and the collection of inhibitors provide a foundation for rational modifications and further development of the compounds.},
keywords = {MANTIS},
pubstate = {published},
tppubtype = {article}
}
ADP-ribosylation is an enzymatic process where an ADP-ribose moiety is transferred from NAD+ to an acceptor molecule. While ADP-ribosylation is well-established as a post-translational modification of proteins, rifamycin antibiotics are its only known small-molecule targets. ADP-ribosylation of rifampicin was first identified in Mycolicibacterium smegmatis, whose Arr enzyme transfers the ADP-ribose moiety to the 23-hydroxy group of rifampicin preventing its interaction with the bacterial RNA polymerase thereby inactivating the antibiotic. Arr homologues are widely spread among bacterial species and present in several pathogenic species often associated with mobile genetic elements. Inhibition of Arr enzymes offers a promising strategy to overcome ADP-ribosylation mediated rifamycin resistance. We developed a high-throughput activity assay, which was applied to screen an in-house library of human ADP-ribosyltransferase-targeted compounds. We identified 15 inhibitors with IC50 values below 5 µM against four Arr enzymes from M. smegmatis, Pseudomonas aeruginosa, Stenotrophomonas maltophilia and Mycobacteroides abscessus. The observed overall selectivity of the hit compounds over the other homologues indicated structural differences between the proteins. We crystallized M. smegmatis and P. aeruginosa Arr enzymes, the former in complex with its most potent hit compound with an IC50 value of 1.3 µM. We observed structural differences in the NAD+ binding pockets of the two Arr homologues explaining the selectivity. Although the Arr inhibitors did not sensitize M. smegmatis to rifampicin in a growth inhibition assay, the structural information and the collection of inhibitors provide a foundation for rational modifications and further development of the compounds. |
Richardson, Miles SAMPL-seq reveals micron-scale spatial hubs in the human gut microbiome Journal Article In: 2025. @article{noKey,
title = {SAMPL-seq reveals micron-scale spatial hubs in the human gut microbiome},
author = {Richardson, Miles},
url = {https://www.nature.com/articles/s41564-024-01914-4},
doi = {https://doi.org/10.1038/s41564-024-01914-4},
year = {2025},
date = {2025-02-11},
abstract = {The local arrangement of microbes can profoundly impact community assembly, function and stability. However, our understanding of the spatial organization of the human gut microbiome at the micron scale is limited. Here we describe a high-throughput and streamlined method called Split-And-pool Metagenomic Plot-sampling sequencing (SAMPL-seq) to capture spatial co-localization in a complex microbial consortium. The method obtains microbial composition of micron-scale subcommunities through split-and-pool barcoding. SAMPL-seq analysis of the healthy human gut microbiome identified bacterial taxa pairs that consistently co-occurred both over time and across multiple individuals. These co-localized microbes organize into spatially distinct groups or ‘spatial hubs’ dominated by Bacteroidaceae, Ruminococcaceae and Lachnospiraceae families. Using inulin as a dietary perturbation, we observed reversible spatial rearrangement of the gut microbiome where specific taxa form new local partnerships. Spatial metagenomics using SAMPL-seq can unlock insights into microbiomes at the micron scale.},
keywords = {MANTIS},
pubstate = {published},
tppubtype = {article}
}
The local arrangement of microbes can profoundly impact community assembly, function and stability. However, our understanding of the spatial organization of the human gut microbiome at the micron scale is limited. Here we describe a high-throughput and streamlined method called Split-And-pool Metagenomic Plot-sampling sequencing (SAMPL-seq) to capture spatial co-localization in a complex microbial consortium. The method obtains microbial composition of micron-scale subcommunities through split-and-pool barcoding. SAMPL-seq analysis of the healthy human gut microbiome identified bacterial taxa pairs that consistently co-occurred both over time and across multiple individuals. These co-localized microbes organize into spatially distinct groups or ‘spatial hubs’ dominated by Bacteroidaceae, Ruminococcaceae and Lachnospiraceae families. Using inulin as a dietary perturbation, we observed reversible spatial rearrangement of the gut microbiome where specific taxa form new local partnerships. Spatial metagenomics using SAMPL-seq can unlock insights into microbiomes at the micron scale. |
Hiang Ling, Lay Sustainable Biosynthesis of Diverse Fatty Acid Esters of Hydroxy Fatty Acids (FAHFAs) for Industrial Production Journal Article In: 2025. @article{noKey,
title = {Sustainable Biosynthesis of Diverse Fatty Acid Esters of Hydroxy Fatty Acids (FAHFAs) for Industrial Production},
author = {Hiang Ling, Lay},
url = {https://pubs.acs.org/doi/full/10.1021/acssuschemeng.4c08793},
doi = {https://doi.org/10.1021/acssuschemeng.4c08793},
year = {2025},
date = {2025-02-11},
abstract = {Fatty acid esters of hydroxy fatty acids (FAHFAs) are a newly discovered lipid class known for their potential anti-inflammatory and insulin-sensitizing properties. A sustainable and efficient synthesis route is essential to realize the potential of FAHFAs and enable cost-effective, large-scale production. Enzymatic synthesis, favored for its scalability and environmental impact, is the preferred approach. Candida (Moesziomyces) antarctica lipase A (CalA), previously known for its thermostability and limited ability to catalyze FAHFA esterification, was investigated along with its orthologues for their ability to produce a variety of FAHFAs. We developed a systematic workflow to identify uncharacterized enzymes for FAHFA synthesis from natural sources, using an automation-compatible method, leading to the discovery of several novel lipases capable of synthesizing diverse FAHFAs. Among these lipases, two newly discovered enzymes, CL20 and CL23, demonstrated superior performance in FAHFA biosynthesis, achieving faster and higher yields than the benchmark enzyme, CalA. Our work advances methodologies and processes critical for industrial FAHFA production and provides a foundation for sustainable commercial-scale synthesis via synthetic enzymology.},
keywords = {NT8},
pubstate = {published},
tppubtype = {article}
}
Fatty acid esters of hydroxy fatty acids (FAHFAs) are a newly discovered lipid class known for their potential anti-inflammatory and insulin-sensitizing properties. A sustainable and efficient synthesis route is essential to realize the potential of FAHFAs and enable cost-effective, large-scale production. Enzymatic synthesis, favored for its scalability and environmental impact, is the preferred approach. Candida (Moesziomyces) antarctica lipase A (CalA), previously known for its thermostability and limited ability to catalyze FAHFA esterification, was investigated along with its orthologues for their ability to produce a variety of FAHFAs. We developed a systematic workflow to identify uncharacterized enzymes for FAHFA synthesis from natural sources, using an automation-compatible method, leading to the discovery of several novel lipases capable of synthesizing diverse FAHFAs. Among these lipases, two newly discovered enzymes, CL20 and CL23, demonstrated superior performance in FAHFA biosynthesis, achieving faster and higher yields than the benchmark enzyme, CalA. Our work advances methodologies and processes critical for industrial FAHFA production and provides a foundation for sustainable commercial-scale synthesis via synthetic enzymology. |
S. Mpontshane, Nokwanda Heterologous production, purification and crystallization of 24C-sterol methyltransferase from Candida albicans Journal Article In: 2025. @article{noKey,
title = {Heterologous production, purification and crystallization of 24C-sterol methyltransferase from Candida albicans},
author = {S. Mpontshane, Nokwanda},
url = {https://www.biorxiv.org/content/10.1101/2025.02.05.636639v1.abstract},
doi = {https://doi.org/10.1101/2025.02.05.636639},
year = {2025},
date = {2025-02-05},
abstract = {Candida albicans is a critical priority fungal pathogen causing invasive fungal infections with high mortality rates in immunocompromised patients. The increasing fungal infection rate and resistance of fungal pathogens to existing antifungal treatments have emphasized the need for the development of novel antifungal medicine. The ergosterol biosynthesis pathway has been a successful target for antifungal compounds, but many enzymatic steps remain unexplored. 24C-sterol methyltransferase (24C-SMT) catalyzes a critical fungal-specific step in ergosterol biosynthesis. When 24C-SMT is disrupted, fungal pathogens are sensitized to temperature, various inhibitors, and antifungals, and a loss of virulence can be observed. In this study, five 24C-SMT variants with different lengths of N-termini were heterologously produced in Escherichia coli and three were purified to near-homogeneity with immobilized metal-affinity and size-exclusion chromatography. N-terminally truncated C. albicans 24C-SMT was utilized for crystallization trials due to its increased stability and higher purity compared to the full-length protein. 24C-SMT crystals were obtained in the presence of Sadenosyl-homocysteine, but diffracted to low resolution. Therefore, we established a starting point for 24C-SMT crystallization by providing an optimized protocol for heterologous 24C-SMT production, purification and initial crystallization conditions, which could be used for further downstream crystallographic studies.},
keywords = {FORMULATOR},
pubstate = {published},
tppubtype = {article}
}
Candida albicans is a critical priority fungal pathogen causing invasive fungal infections with high mortality rates in immunocompromised patients. The increasing fungal infection rate and resistance of fungal pathogens to existing antifungal treatments have emphasized the need for the development of novel antifungal medicine. The ergosterol biosynthesis pathway has been a successful target for antifungal compounds, but many enzymatic steps remain unexplored. 24C-sterol methyltransferase (24C-SMT) catalyzes a critical fungal-specific step in ergosterol biosynthesis. When 24C-SMT is disrupted, fungal pathogens are sensitized to temperature, various inhibitors, and antifungals, and a loss of virulence can be observed. In this study, five 24C-SMT variants with different lengths of N-termini were heterologously produced in Escherichia coli and three were purified to near-homogeneity with immobilized metal-affinity and size-exclusion chromatography. N-terminally truncated C. albicans 24C-SMT was utilized for crystallization trials due to its increased stability and higher purity compared to the full-length protein. 24C-SMT crystals were obtained in the presence of Sadenosyl-homocysteine, but diffracted to low resolution. Therefore, we established a starting point for 24C-SMT crystallization by providing an optimized protocol for heterologous 24C-SMT production, purification and initial crystallization conditions, which could be used for further downstream crystallographic studies. |
Angelos Stamos, Nikolaos Beyond Barriers, Big Crystallisation Hurdles: Atropisomerism in bRo5 Compounds Explored by Computational and NMR Studies Journal Article In: 2025. @article{noKey,
title = {Beyond Barriers, Big Crystallisation Hurdles: Atropisomerism in bRo5 Compounds Explored by Computational and NMR Studies},
author = {Angelos Stamos, Nikolaos},
url = {https://chemrxiv.org/engage/chemrxiv/article-details/679a3f956dde43c908d979c7},
doi = {https://doi.org/10.26434/chemrxiv-2025-rz4q6},
year = {2025},
date = {2025-02-03},
abstract = {Crystallisation and stereochemical stability are pivotal factors in pharmaceutical development, particularly for complex beyond Rule of 5 (bRo5) compounds. In this study, we explore the intricate interplay between atropisomerism and crystallisation using two model bRo5 compounds, namely ACBI1 and BI201335, both violating three of four Lipinski’s rules. One of the tool compounds exhibits Class 2 atropisomeric behaviour and the other devoid of it. A diverse array of crystallisation methods—including solution-phase crystallisation, cocrystallisation, and salt formation—was applied, revealing the critical role of atropisomerism induced stereochemistry in polymorphism and nucleation outcomes. In-silico torsion profile calculations and NMR studies were employed to elucidate the rotational energy barriers and confirm the presence or absence of atropisomerism. This comprehensive analysis highlights the significance of understanding stereochemical phenomena like atropisomerism in designing and developing bRo5 compounds. By integrating advanced analytical techniques and crystallisation strategies, this work provides novel insights into tailoring pharmaceutical properties for nextgeneration therapeutics.},
keywords = {ROCKIMAGER},
pubstate = {published},
tppubtype = {article}
}
Crystallisation and stereochemical stability are pivotal factors in pharmaceutical development, particularly for complex beyond Rule of 5 (bRo5) compounds. In this study, we explore the intricate interplay between atropisomerism and crystallisation using two model bRo5 compounds, namely ACBI1 and BI201335, both violating three of four Lipinski’s rules. One of the tool compounds exhibits Class 2 atropisomeric behaviour and the other devoid of it. A diverse array of crystallisation methods—including solution-phase crystallisation, cocrystallisation, and salt formation—was applied, revealing the critical role of atropisomerism induced stereochemistry in polymorphism and nucleation outcomes. In-silico torsion profile calculations and NMR studies were employed to elucidate the rotational energy barriers and confirm the presence or absence of atropisomerism. This comprehensive analysis highlights the significance of understanding stereochemical phenomena like atropisomerism in designing and developing bRo5 compounds. By integrating advanced analytical techniques and crystallisation strategies, this work provides novel insights into tailoring pharmaceutical properties for nextgeneration therapeutics. |
Tan, Jeremiah, Bernatsky, Sasha, et al. COVID-19 Breakthrough Infections in Immune-Mediated Inflammatory Diseases: Data from the SUCCEED (Safety and Immunogenicity of COVID-19 Vaccines in Systemic Autoimmune-Mediated Inflammatory Diseases) Study Journal Article In: 2025. @article{noKey,
title = {COVID-19 Breakthrough Infections in Immune-Mediated Inflammatory Diseases: Data from the SUCCEED (Safety and Immunogenicity of COVID-19 Vaccines in Systemic Autoimmune-Mediated Inflammatory Diseases) Study},
author = {Tan, Jeremiah, Bernatsky, Sasha, et al.},
url = {https://www.mdpi.com/2076-393X/13/2/104},
doi = {https://doi.org/10.3390/vaccines13020104},
year = {2025},
date = {2025-01-22},
abstract = {ackground: The Safety and Immunogenicity of COVID-19 Vaccines in Systemic Autoimmune-Mediated Inflammatory Diseases (SUCCEED) study was created to better understand COVID-19 vaccination in immune-mediated inflammatory disease (IMID). Knowing the frequency of COVID-19 breakthrough infections is important, particularly in IMID. Our objective was to assess these events in IMID. Methods: We prospectively studied IMID participants who had received ≥three COVID-19 vaccine doses. Individuals provided saliva samples monthly (September 2022 to August 2023). These were evaluated by polymerase chain reaction (PCR) for SARS-CoV-2. We also assessed antibodies against SARS-CoV-2 (anti-spike, SmT1, receptor binding domain, RBD, and nucleocapsid, NP) based on dried blood spots. Multivariable general estimating equation regression produced odd ratios (OR) for PCR SARS-CoV-2 positivity, related to demographics, immunosuppressives, and antibody levels. Results: Diagnoses included rheumatoid arthritis RA (N = 161, 44% of the total), systemic lupus, psoriatic arthritis, spondylarthritis, vasculitis, systemic sclerosis, and inflammatory bowel disease. Of the 366 participants, most were taking immunosuppressive medication. Of 1266 saliva samples, 56 (5.1%) were positive for SARS-CoV-2 on PCR. Higher anti-SmT1 antibodies were inversely associated with SARS-CoV-2 detection on PCR (adjusted OR 0.66, 95% confidence interval 0.45–0.97). Antibodies to SmT1, RBD, and NP were correlated and thus could not be included in a single model, but when anti-RBD was used in place of anti-SmT1, the results were similar. No other factor (including prior COVID-19 infection) was clearly associated with SARS-CoV-2 detection. Conclusions: This is the first study of SARS-CoV-2 in a large prospective cohort of triple (or more) vaccinated individuals with IMIDs. Anti-SmT1 antibodies appeared to be protective against later SARS-CoV-2 positivity, although recent past infection was not clearly related. This suggests the importance of maintaining robust vaccine-induced immunity through vaccination in IMID.},
keywords = {MANTIS},
pubstate = {published},
tppubtype = {article}
}
ackground: The Safety and Immunogenicity of COVID-19 Vaccines in Systemic Autoimmune-Mediated Inflammatory Diseases (SUCCEED) study was created to better understand COVID-19 vaccination in immune-mediated inflammatory disease (IMID). Knowing the frequency of COVID-19 breakthrough infections is important, particularly in IMID. Our objective was to assess these events in IMID. Methods: We prospectively studied IMID participants who had received ≥three COVID-19 vaccine doses. Individuals provided saliva samples monthly (September 2022 to August 2023). These were evaluated by polymerase chain reaction (PCR) for SARS-CoV-2. We also assessed antibodies against SARS-CoV-2 (anti-spike, SmT1, receptor binding domain, RBD, and nucleocapsid, NP) based on dried blood spots. Multivariable general estimating equation regression produced odd ratios (OR) for PCR SARS-CoV-2 positivity, related to demographics, immunosuppressives, and antibody levels. Results: Diagnoses included rheumatoid arthritis RA (N = 161, 44% of the total), systemic lupus, psoriatic arthritis, spondylarthritis, vasculitis, systemic sclerosis, and inflammatory bowel disease. Of the 366 participants, most were taking immunosuppressive medication. Of 1266 saliva samples, 56 (5.1%) were positive for SARS-CoV-2 on PCR. Higher anti-SmT1 antibodies were inversely associated with SARS-CoV-2 detection on PCR (adjusted OR 0.66, 95% confidence interval 0.45–0.97). Antibodies to SmT1, RBD, and NP were correlated and thus could not be included in a single model, but when anti-RBD was used in place of anti-SmT1, the results were similar. No other factor (including prior COVID-19 infection) was clearly associated with SARS-CoV-2 detection. Conclusions: This is the first study of SARS-CoV-2 in a large prospective cohort of triple (or more) vaccinated individuals with IMIDs. Anti-SmT1 antibodies appeared to be protective against later SARS-CoV-2 positivity, although recent past infection was not clearly related. This suggests the importance of maintaining robust vaccine-induced immunity through vaccination in IMID. |
Xin et al., Lun Rapid Development of High Concentration Protein Formulation Driven by High-Throughput Technologies Journal Article In: 2025. @article{noKey,
title = {Rapid Development of High Concentration Protein Formulation Driven by High-Throughput Technologies},
author = {Xin et al., Lun},
url = {https://link.springer.com/article/10.1007/s11095-024-03801-3},
doi = {https://doi.org/10.1007/s11095-024-03801-3},
year = {2025},
date = {2025-01-17},
abstract = {Background High concentration protein formulation (HCPF) development needs to balance protein stability attributes such
as conformational/colloidal stability, chemical stability, and solution properties such as viscosity and osmolality.
Methodology A three-phase design is established in this work. In Phase 1, conformational and colloidal stability are measured by 384-well-based high-throughput (HT) biophysical screening while viscosity reduction screening is performed with HT viscosity screening. Collectively, the biophysical and viscosity screening data are leveraged to design the phase 2 of short-term stability study, executed using 96-well plates under thermal and freeze/thaw stresses. In phase 2, samples are analyzed by stability-indicating assays and processed with pair-wise Student’s t-test analyses to choose the final formulations. In phase 3, the final formulations are then confirmed through a one-month accelerated stability in glass vials.
Results Using a model antibody A (mAb-A), the initial HT screening successfully established the 384-well based platform.
A lead formulation was chosen from the second round based on statistical analyses and subsequently tested against the commercial
formulation of mAb-A as a control. Compared to the control, the lead formulation reduced the viscosity of mAb-A by 30% and decreased subvisible particles after thermal stress by 80%.
Conclusions HT biophysical screening in 384-well plates was demonstrated to effectively guide the rational design of a high-throughput stability screening study using 96-well plates. This platform enables the identification of a high concentration formulation within seven weeks within the first two phases of study that strategically balance stability with solution
properties, thus achieving a rapid development of HCPF.},
keywords = {µPULSE},
pubstate = {published},
tppubtype = {article}
}
Background High concentration protein formulation (HCPF) development needs to balance protein stability attributes such
as conformational/colloidal stability, chemical stability, and solution properties such as viscosity and osmolality.
Methodology A three-phase design is established in this work. In Phase 1, conformational and colloidal stability are measured by 384-well-based high-throughput (HT) biophysical screening while viscosity reduction screening is performed with HT viscosity screening. Collectively, the biophysical and viscosity screening data are leveraged to design the phase 2 of short-term stability study, executed using 96-well plates under thermal and freeze/thaw stresses. In phase 2, samples are analyzed by stability-indicating assays and processed with pair-wise Student’s t-test analyses to choose the final formulations. In phase 3, the final formulations are then confirmed through a one-month accelerated stability in glass vials.
Results Using a model antibody A (mAb-A), the initial HT screening successfully established the 384-well based platform.
A lead formulation was chosen from the second round based on statistical analyses and subsequently tested against the commercial
formulation of mAb-A as a control. Compared to the control, the lead formulation reduced the viscosity of mAb-A by 30% and decreased subvisible particles after thermal stress by 80%.
Conclusions HT biophysical screening in 384-well plates was demonstrated to effectively guide the rational design of a high-throughput stability screening study using 96-well plates. This platform enables the identification of a high concentration formulation within seven weeks within the first two phases of study that strategically balance stability with solution
properties, thus achieving a rapid development of HCPF. |
Wright, Gerard A microbial natural product fractionation library screen with HRMS/MS dereplication identifies new lipopeptaibiotics against Candida auris Journal Article In: 2025. @article{noKey,
title = {A microbial natural product fractionation library screen with HRMS/MS dereplication identifies new lipopeptaibiotics against Candida auris},
author = {Wright, Gerard},
url = {https://www.researchsquare.com/article/rs-5802877/v1},
doi = {https://doi.org/10.21203/rs.3.rs-5802877/v1},
year = {2025},
date = {2025-01-16},
abstract = {The rise of drug-resistant fungal pathogens, including Candida auris, highlights the urgent need for novel antifungal therapies. We developed a cost-effective platform combining microbial extract prefractionation with rapid MS/MS-bioinformatics-based dereplication to efficiently prioritize new antifungal scaffolds. Screening C. auris and C. albicans revealed novel lipopeptaibiotics, coniotins, from Coniochaeta hoffmannii WAC11161, which were undetectable in crude extracts. Coniotins exhibited potent activity against critical fungal pathogens on the WHO Fungal Priority Pathogens List, including C. albicans, C. neoformans, multidrug-resistant C. auris, and Aspergillus fumigatus, with high selectivity and low resistance potential. Coniotin A targets β-glucan, compromising fungal cell wall integrity, remodelling, and sensitizing C. auris to caspofungin. Identification of a PKS-NRPS biosynthetic gene cluster further enables the discovery of related clusters encoding potential novel lipopeptaibiotics. This study demonstrates the power of natural product prefractionation in uncovering bioactive scaffolds and introduces coniotins as promising candidates for combating multidrug-resistant fungal pathogens.},
keywords = {TEMPEST},
pubstate = {published},
tppubtype = {article}
}
The rise of drug-resistant fungal pathogens, including Candida auris, highlights the urgent need for novel antifungal therapies. We developed a cost-effective platform combining microbial extract prefractionation with rapid MS/MS-bioinformatics-based dereplication to efficiently prioritize new antifungal scaffolds. Screening C. auris and C. albicans revealed novel lipopeptaibiotics, coniotins, from Coniochaeta hoffmannii WAC11161, which were undetectable in crude extracts. Coniotins exhibited potent activity against critical fungal pathogens on the WHO Fungal Priority Pathogens List, including C. albicans, C. neoformans, multidrug-resistant C. auris, and Aspergillus fumigatus, with high selectivity and low resistance potential. Coniotin A targets β-glucan, compromising fungal cell wall integrity, remodelling, and sensitizing C. auris to caspofungin. Identification of a PKS-NRPS biosynthetic gene cluster further enables the discovery of related clusters encoding potential novel lipopeptaibiotics. This study demonstrates the power of natural product prefractionation in uncovering bioactive scaffolds and introduces coniotins as promising candidates for combating multidrug-resistant fungal pathogens. |
Duong, Tam Three-dimensional linkage analysis with digital PCR for genome integrity and identity of recombinant adeno-associated virus Journal Article In: 2025. @article{noKey,
title = {Three-dimensional linkage analysis with digital PCR for genome integrity and identity of recombinant adeno-associated virus},
author = {Duong, Tam},
url = {https://www.nature.com/articles/s41598-024-77378-7},
doi = {https://doi.org/10.1038/s41598-024-77378-7},
year = {2025},
date = {2025-01-16},
abstract = {Recombinant adeno-associated virus (rAAV) has emerged as the vector of choice for in vivo gene delivery, with numerous clinical trials underway for the treatment of various human diseases. Utilizing rAAV in gene therapy requires a highly precise quantification method to determine the viral genome titer and further establish the optimal therapeutic dosage for a rAAV product. The conventional single-channel droplet digital PCR (1D ddPCR) method offers only partial information regarding the viral vector genome titer, lacking insights into its integrity. In our pursuit of further advancing rAAV analysis, we have developed a novel 3D ddPCR assay with advanced 3D linkage analysis. We have designed the three amplicon sites targeting both ends of the viral genome, as well as the center of key therapeutic gene of interest (GOI). This study aims to offer a more comprehensive and insightful assessment of rAAV products which includes not only quantity of viral genome titer but also the quality, distinguishing between partial ones and intact full-length viral genomes with the right GOI. Importantly, due to the random partitioning property of a digital PCR system, the 3D linkage analysis of rAAV viral genome requires a proper mathematical model to identify the true linked DNA molecules (full-length/intact DNA) from the population of false/unlinked DNA molecules (fragmented/partial DNA). We therefore have developed an AAV 3D linkage analysis workflow to characterize genomic integrity and intact titer for rAAV gene therapy products. In this study, we focus on evaluating our 3D linkage mathematical model by performing DNA mixing experiments and a case study using multiple rAAV samples. Particularly, we rigorously tested our algorithms by conducting experiments involving the mixing of seven DNA fragments to represent various AAV viral genome populations, including 3 single partials, 3 double partials, and 1 full-length genomes. Across all 37 tested scenarios, we validated the accuracy of our workflow’s output for the percentages of 3D linkage by comparing to the known percentages of input DNA. Consequently, our comprehensive AAV analytical package not only offers insights into viral genome titer but also provides valuable information on its integrity and identity. This cost-effective approach, akin to the setup of traditional 1D or 2D dPCR, holds the potential to advance the application of rAAV in cell and gene therapy for the treatment of human diseases.},
keywords = {MANTIS},
pubstate = {published},
tppubtype = {article}
}
Recombinant adeno-associated virus (rAAV) has emerged as the vector of choice for in vivo gene delivery, with numerous clinical trials underway for the treatment of various human diseases. Utilizing rAAV in gene therapy requires a highly precise quantification method to determine the viral genome titer and further establish the optimal therapeutic dosage for a rAAV product. The conventional single-channel droplet digital PCR (1D ddPCR) method offers only partial information regarding the viral vector genome titer, lacking insights into its integrity. In our pursuit of further advancing rAAV analysis, we have developed a novel 3D ddPCR assay with advanced 3D linkage analysis. We have designed the three amplicon sites targeting both ends of the viral genome, as well as the center of key therapeutic gene of interest (GOI). This study aims to offer a more comprehensive and insightful assessment of rAAV products which includes not only quantity of viral genome titer but also the quality, distinguishing between partial ones and intact full-length viral genomes with the right GOI. Importantly, due to the random partitioning property of a digital PCR system, the 3D linkage analysis of rAAV viral genome requires a proper mathematical model to identify the true linked DNA molecules (full-length/intact DNA) from the population of false/unlinked DNA molecules (fragmented/partial DNA). We therefore have developed an AAV 3D linkage analysis workflow to characterize genomic integrity and intact titer for rAAV gene therapy products. In this study, we focus on evaluating our 3D linkage mathematical model by performing DNA mixing experiments and a case study using multiple rAAV samples. Particularly, we rigorously tested our algorithms by conducting experiments involving the mixing of seven DNA fragments to represent various AAV viral genome populations, including 3 single partials, 3 double partials, and 1 full-length genomes. Across all 37 tested scenarios, we validated the accuracy of our workflow’s output for the percentages of 3D linkage by comparing to the known percentages of input DNA. Consequently, our comprehensive AAV analytical package not only offers insights into viral genome titer but also provides valuable information on its integrity and identity. This cost-effective approach, akin to the setup of traditional 1D or 2D dPCR, holds the potential to advance the application of rAAV in cell and gene therapy for the treatment of human diseases. |
M. Böhm, Jonas From dimer to tetramer: the evolutionary trajectory of C4 photosynthetic-NADP-ME oligomeric state in Poaceae Journal Article In: 2025. @article{noKey,
title = {From dimer to tetramer: the evolutionary trajectory of C4 photosynthetic-NADP-ME oligomeric state in Poaceae},
author = {M. Böhm, Jonas},
url = {https://www.biorxiv.org/content/10.1101/2025.01.05.631420v1.abstract},
doi = {https://doi.org/10.1101/2025.01.05.631420},
year = {2025},
date = {2025-01-06},
abstract = {The C4 carbon concentrating mechanism relies on specialized enzymes that have evolved unique expression patterns and biochemical properties distinct to their ancestral housekeeping forms. In maize and sorghum, the evolution of C4-NADP-malic enzyme (C4-NADP-ME) involved gene duplication and neofunctionalization, leading to the emergence of two plastidic isoforms: C4-NADP-ME and nonC4-NADP-ME, each with distinct kinetic and structural features. While C4-NADP-ME functions primarily as a tetramer, nonC4-NADP-ME exists in an equilibrium between dimeric and tetrameric forms, favoring the dimer in solution. This study shows which evolutionary changes in amino acid sequences influence the structure and function of these isoforms. By integrating X-ray crystallography, cryo-electron microscopy, computational molecular modeling and targeted biochemical analysis of mutant and truncated protein variants, we identify crucial roles for the N- and C-terminal regions and specific amino acid residues in governing isoform oligomerization. Our results reveal that the N-terminal region is essential for stabilizing the dimeric form of nonC4-NADP-ME, whereas specific adaptive substitutions and interactions with the C-terminal region enhance the stability of the tetrameric state characteristic of the C4-adapted isoform. We propose that differences in the N-terminal domain between the C4 and nonC4 isoforms reflect distinct selective pressures, which have driven their evolutionary divergence to fulfill specialized cellular functions.},
keywords = {ROCKIMAGER},
pubstate = {published},
tppubtype = {article}
}
The C4 carbon concentrating mechanism relies on specialized enzymes that have evolved unique expression patterns and biochemical properties distinct to their ancestral housekeeping forms. In maize and sorghum, the evolution of C4-NADP-malic enzyme (C4-NADP-ME) involved gene duplication and neofunctionalization, leading to the emergence of two plastidic isoforms: C4-NADP-ME and nonC4-NADP-ME, each with distinct kinetic and structural features. While C4-NADP-ME functions primarily as a tetramer, nonC4-NADP-ME exists in an equilibrium between dimeric and tetrameric forms, favoring the dimer in solution. This study shows which evolutionary changes in amino acid sequences influence the structure and function of these isoforms. By integrating X-ray crystallography, cryo-electron microscopy, computational molecular modeling and targeted biochemical analysis of mutant and truncated protein variants, we identify crucial roles for the N- and C-terminal regions and specific amino acid residues in governing isoform oligomerization. Our results reveal that the N-terminal region is essential for stabilizing the dimeric form of nonC4-NADP-ME, whereas specific adaptive substitutions and interactions with the C-terminal region enhance the stability of the tetrameric state characteristic of the C4-adapted isoform. We propose that differences in the N-terminal domain between the C4 and nonC4 isoforms reflect distinct selective pressures, which have driven their evolutionary divergence to fulfill specialized cellular functions. |
Krysan, Damian Discovery and mechanism of a highly selective, antifungal acetyl CoA synthetase inhibitor Journal Article In: 2025. @article{noKey,
title = {Discovery and mechanism of a highly selective, antifungal acetyl CoA synthetase inhibitor},
author = {Krysan, Damian},
url = {https://www.researchsquare.com/article/rs-5619443/v1},
doi = {https://doi.org/10.21203/rs.3.rs-5619443/v1},
year = {2025},
date = {2025-01-01},
abstract = {Acetyl CoA synthetases (ACS) have emerged as drug targets for the treatment of cancer, metabolic diseases as well as fungal and parasitic infections. Although a variety of small molecule ACS inhibitors have been discovered, the systematic optimization of these molecules has been slowed by a lack of structural information regarding their mechanism of inhibition. Through a chemical genetic-based, synthetic lethal screen of the human fungal pathogen Cryptococcus neoformans, we identified an isoxazole-based ACS inhibitor with antifungal activity and exquisite selectivity for the C. neoformans Acs1 relative to human ACSS2 as well as other fungal ACSs. Xray crystallographic characterization of the isoxazole-CnAcs1 complex revealed that the isoxazole functions as an acetyl CoA mimic and occupies both the acetyl- and CoA-binding sites of CnAcs1. Consistent with this novel mode of inhibition, the isoxazoles display uncompetitive inhibition kinetics that are similar to antimalarial ACS inhibitors also proposed to target the CoA binding site. Consequently, these data provide structural and mechanistic insights into the remarkable selectivity of Acetyl CoA pocket-targeting ACS inhibitors. In addition, these data provide strong proof-of-principle that targeting fungal and parasitic ACSs for the development of novel anti-infectives can be achieved with high selectivity and, thereby, low host toxicity.},
keywords = {NT8},
pubstate = {published},
tppubtype = {article}
}
Acetyl CoA synthetases (ACS) have emerged as drug targets for the treatment of cancer, metabolic diseases as well as fungal and parasitic infections. Although a variety of small molecule ACS inhibitors have been discovered, the systematic optimization of these molecules has been slowed by a lack of structural information regarding their mechanism of inhibition. Through a chemical genetic-based, synthetic lethal screen of the human fungal pathogen Cryptococcus neoformans, we identified an isoxazole-based ACS inhibitor with antifungal activity and exquisite selectivity for the C. neoformans Acs1 relative to human ACSS2 as well as other fungal ACSs. Xray crystallographic characterization of the isoxazole-CnAcs1 complex revealed that the isoxazole functions as an acetyl CoA mimic and occupies both the acetyl- and CoA-binding sites of CnAcs1. Consistent with this novel mode of inhibition, the isoxazoles display uncompetitive inhibition kinetics that are similar to antimalarial ACS inhibitors also proposed to target the CoA binding site. Consequently, these data provide structural and mechanistic insights into the remarkable selectivity of Acetyl CoA pocket-targeting ACS inhibitors. In addition, these data provide strong proof-of-principle that targeting fungal and parasitic ACSs for the development of novel anti-infectives can be achieved with high selectivity and, thereby, low host toxicity. |
Kaundal, Soni RNA-dependent RNA polymerase of predominant human norovirus forms liquid-liquid phase condensates as viral replication factories Journal Article In: 2024. @article{noKey,
title = {RNA-dependent RNA polymerase of predominant human norovirus forms liquid-liquid phase condensates as viral replication factories},
author = {Kaundal, Soni},
url = {https://www.science.org/doi/full/10.1126/sciadv.adp9333},
doi = {https://doi.org/10.1126/sciadv.adp9333},
year = {2024},
date = {2024-12-20},
abstract = {Many viral proteins form biomolecular condensates via liquid-liquid phase separation (LLPS) to support viral replication and evade host antiviral responses, and thus, they are potential targets for designing antivirals. In the case of nonenveloped positive-sense RNA viruses, forming such condensates for viral replication is unclear and less understood. Human noroviruses (HuNoVs) are positive-sense RNA viruses that cause epidemic and sporadic gastroenteritis worldwide. Here, we show that the RNA-dependent RNA polymerase (RdRp) of pandemic GII.4 HuNoV forms distinct condensates that exhibit all the signature properties of LLPS with sustained polymerase activity and the capability of recruiting components essential for viral replication. We show that such condensates are formed in HuNoV-infected human intestinal enteroid cultures and are the sites for genome replication. Our studies demonstrate the formation of phase-separated condensates as replication factories in a positive-sense RNA virus, which plausibly is an effective mechanism to dynamically isolate RdRp replicating the genomic RNA from interfering with the ribosomal translation of the same RNA.},
keywords = {ROCKIMAGER},
pubstate = {published},
tppubtype = {article}
}
Many viral proteins form biomolecular condensates via liquid-liquid phase separation (LLPS) to support viral replication and evade host antiviral responses, and thus, they are potential targets for designing antivirals. In the case of nonenveloped positive-sense RNA viruses, forming such condensates for viral replication is unclear and less understood. Human noroviruses (HuNoVs) are positive-sense RNA viruses that cause epidemic and sporadic gastroenteritis worldwide. Here, we show that the RNA-dependent RNA polymerase (RdRp) of pandemic GII.4 HuNoV forms distinct condensates that exhibit all the signature properties of LLPS with sustained polymerase activity and the capability of recruiting components essential for viral replication. We show that such condensates are formed in HuNoV-infected human intestinal enteroid cultures and are the sites for genome replication. Our studies demonstrate the formation of phase-separated condensates as replication factories in a positive-sense RNA virus, which plausibly is an effective mechanism to dynamically isolate RdRp replicating the genomic RNA from interfering with the ribosomal translation of the same RNA. |
Dunnett, Louise Enhanced identification of small molecules binding to hnRNPA1 via cryptic pockets mapping coupled with X-Ray fragment screening Journal Article In: 2024. @article{noKey,
title = {Enhanced identification of small molecules binding to hnRNPA1 via cryptic pockets mapping coupled with X-Ray fragment screening},
author = {Dunnett, Louise},
url = {https://www.biorxiv.org/content/10.1101/2024.12.17.628909v1.abstract},
doi = {https://doi.org/10.1101/2024.12.17.628909},
year = {2024},
date = {2024-12-18},
abstract = {The human heterogeneous nuclear ribonucleoprotein (hnRNP) A1 is a prototypical RNA-binding protein essential in regulating a wide range of post-transcriptional events in cells. As a multifunctional protein with a key role in RNA metabolism, deregulation of its functions has been linked to neurodegenerative diseases, tumour aggressiveness and chemoresistance, which has fuelled efforts to develop novel therapeutics that modulates its RNA binding activities. Here, using a combination of Molecular Dynamics (MD) simulations and graph neural network pockets predictions, we showed that hnRNPA1 N-terminal RNA binding domain (UP1) contains several cryptic pockets capable of binding small molecules. To identify chemical entities for development of potent drug candidates and experimentally validate identified druggable hotspots, we carried out a large fragment screening on UP1 protein crystals. Our screen identified 36 hits which extensively samples UP1 functional regions involved in RNA recognition and binding, as well as mapping hotspots onto novel protein interaction surfaces. We observed a wide range of ligand-induced conformational variation, by stabilisation of dynamic protein regions. Our high-resolution structures, the first of an hnRNP in complex with a fragment or small molecule, provides rapid routes for the rational development of a range of different inhibitors and chemical tools for studying molecular mechanisms of hnRNPA1 mediated splicing regulation.},
keywords = {ROCKIMAGER},
pubstate = {published},
tppubtype = {article}
}
The human heterogeneous nuclear ribonucleoprotein (hnRNP) A1 is a prototypical RNA-binding protein essential in regulating a wide range of post-transcriptional events in cells. As a multifunctional protein with a key role in RNA metabolism, deregulation of its functions has been linked to neurodegenerative diseases, tumour aggressiveness and chemoresistance, which has fuelled efforts to develop novel therapeutics that modulates its RNA binding activities. Here, using a combination of Molecular Dynamics (MD) simulations and graph neural network pockets predictions, we showed that hnRNPA1 N-terminal RNA binding domain (UP1) contains several cryptic pockets capable of binding small molecules. To identify chemical entities for development of potent drug candidates and experimentally validate identified druggable hotspots, we carried out a large fragment screening on UP1 protein crystals. Our screen identified 36 hits which extensively samples UP1 functional regions involved in RNA recognition and binding, as well as mapping hotspots onto novel protein interaction surfaces. We observed a wide range of ligand-induced conformational variation, by stabilisation of dynamic protein regions. Our high-resolution structures, the first of an hnRNP in complex with a fragment or small molecule, provides rapid routes for the rational development of a range of different inhibitors and chemical tools for studying molecular mechanisms of hnRNPA1 mediated splicing regulation. |
