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On, Y. Y.

Publications and source records attributed to On, Y. Y..

3 recordsLinked to original sources

GuFi phages represent the most prevalent viral family-level clusters in the human gut microbiome

Despite being important ecological modulators of the gut microbiome, bacteriophage diversity and function remain under-characterized. We show that short-read metagenomic surveys can miss even globally highly prevalent viral family-level clusters (VFCs), that can be readily assembled and characterized with long-read metagenomic data from a relatively small cohort (n=109). While gut Bacteroidota phages have been the prevailing focus in the literature, we show that highly prevalent gut phage families frequently have Firmicutes hosts (termed GuFi phages), with broad host ranges verified using proximity-ligation (Hi-C) sequencing data. High-throughput sequencing of virus-like particles from fecal samples detected frequent enrichment of GuFi phages across samples, revealing their under-appreciated impact on the gut microbiome. We report the first in vitro induction and imaging of members of prevalent GuFi clades including the candidate orders Heliusvirales, Astravirales (VFC 2) and Suryavirales (VFC 4). Our findings underscore the importance of GuFi phages with broad host ranges in the gut microbiome, and the utility of long-read sequencing for viral discovery, paving the way for deeper insights into the role of bacteriophages in human health and disease.

microbiology↗

High-throughput single-cell isolation of Bifidobacterium strains from the gut microbiome

While metagenomic studies can highlight strain-level diversity within microbial communities, the diversity obtained is often incomplete. Moreover, their utility for phenotypic characterizations remains hampered without the subjacent, systematic isolation procedures required with traditional culturomics. In this work, we examined the capabilities of a commercially available high-throughput single-cell dispensing solution to selectively target and isolate diverse strains of a genus of interest, Bifidobacterium, from fecal samples. The general performance of the single-cell dispenser was first assessed, revealing a low doublet frequency of 11.5% and an ability to preserve global genus diversity when a mixed culture of Bifidobacterium was dispensed. Culturing-related factors including the use of an effective selection medium, such as the Bifidus Selective Medium supplemented with mupirocin (BSM-MUP), and the length of incubation were found to be critical in determining isolation success. Leveraging these results, we obtained a total of 622 viable isolates from five Singaporean fecal samples, among which [~]98.7% were bifidobacteria. Whole-genome sequencing of 96 isolates revealed six different Bifidobacterium species with both inter- and intra-subject lineage diversity, and the majority of the assemblies were not previously captured using metagenomic sequencing. Our findings validate the ability of high-throughput culturomics to recover diverse, novel bacterial strains and open up the possibility to robustly interrogate their functional characteristics, advancing our understanding of important microbiomes. IMPORTANCEThe field of microbial culturomics is still in its early stages. Enhancing our ability to isolate and phenotypically test bacterial strains from their multicellular environment is crucial for advancing microbiome research and healthcare development. Given the time- and cost-inefficiencies of traditional culturing methods, a more efficient, high-throughput approach to obtain isolates is needed. In the present study, we assessed a single-cell dispensing platform and developed a workflow to isolate diverse Bifidobacterium strains from fecal samples. We demonstrated here the capability of this novel technology to efficiently obtain hundreds of isolates of a targeted organism, covering both species and strain diversities. This generalizable and scalable method allows for the high-throughput recovery of microbes with little optimization needed for novel targets, providing a fundamental step in improving the culturomic framework to complement metagenomic approaches and enable isolate-level functional studies of important microbiomes.

microbiology↗

Large-scale skin metagenomics reveals extensive prevalence, coordination, and functional adaptation of skin microbiome dermotypes across body sites

While skin microbiome studies have increasingly highlighted its importance in health and disease, our understanding of inter-individual heterogeneity in structure and function remains limited, impacting the ability to develop microbiome-based stratification and therapeutics. Powered by comprehensive skin microbiome characterization in a multi-ethnic population-based cohort (>3,550 shotgun metagenomes across 18 sampling sites), we established significant undescribed inter-individual heterogeneity and the extensive prevalence of distinct microbial configurations (17 species-resolution dermotypes) in seven out of nine body sites. Combining functional in silico and in vitro studies revealed insights into how these dermotypes assemble as a function of niche-dependent microbial interactions (e.g. hypoxia-dependent inhibition of S. hominis by S. epidermidis/M. luteus) and metabolic resource utilization (e.g. differential galactose and histidine metabolism). Integration of demographic, skin physiological, and behavioral data further identified >30 significant associations with host attributes. Cross-site analysis revealed remarkable coordination across disparate skin regions (predictive AUC-ROC>0.8) and bilateral consistency (Pearson {pi}>0.95), emphasizing the role of specific microbial and host factors in shaping dermotypes. Finally, we provide multiple lines of evidence that dermotype states impact the risk for skin discomfort (e.g. irritation, itch) and diseases (e.g. eczema), that when combined with our highly accurate dermotype classifiers (AUC-ROC>0.98), provide a new paradigm for understanding skin microbiome function and stratifying patients in the context of skin and other diseases.

genomics↗