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  • Falk Sweet posted an update 10 months, 3 weeks ago

    structures of individual viromes. In this study, we identified 24 putative CRISPR arrays using a shotgun metagenome data set of the human skin microbiome. The findings of this study expand our understanding of the nature of CRISPRs by identifying novel CRISPR candidates. We developed a method to efficiently determine the diversity of three CRISPR arrays. Our analysis revealed that the CRISPR spacer diversity in the human skin microbiome is highly personalized compared with the microbiome diversity assessed by 16S rRNA sequencing, providing a new perspective on the study of the skin microbiome.Candida albicans is the most common human fungal pathogen, causing diseases ranging from mucosal to systemic infections for both immunocompetent and immunocompromised individuals. Lysine 2-hydroxyisobutyrylation is a highly conserved posttranslational modification found in a wide variety of organisms. In this study, we surveyed the biological impact of 2-hydroxyisobutyrylation on lysine residuals (Khib) in C. albicans Using an antibody enrichment approach along with the traditional liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, we analyzed the pattern of Khib-modified proteins and sites in one wild-type strain of C. albicans We identified 1,438 Khib-modified proteins with 6,659 modified sites in this strain, and a more detailed bioinformatics analysis indicated that the Khib-modified proteins are involved in a wide range of cellular functions with diverse subcellular locations. Functional enrichment analysis featured several prominent functional pathways, including ribosome, biosynthesis ofwhich has been linked to many pathogenic events, including cancers. The types of PTM and their pathogenic roles in C. albicans are still somewhat poorly understood, even though studies of C. albicans based on acetylation inhibitors have shed some light on their function, and it seems that PTMs regulate pathogenic adhesion factors. Here, we quantified and analyzed the occurrence of lysine 2-hydroxyisobutyrylation (Khib) in C. albicans The Khib-modified proteins are enriched with respect to carbon metabolism, ribosomal biogenesis, and protein translation in C. albicans.Host-associated microbes display remarkable convergence in genome repertoire resulting from selection to supplement missing host functions. Nutritional supplementation has been proposed in the verrucomicrobial endosymbiont Xiphinematobacter sp., which lives within a globally widespread group of plant-parasitic nematodes that vector damaging nepoviruses to plants. Only one genome sequence has been published from this symbiont, leaving unanswered questions about its diversity, host range, role, and selective pressures within its hosts. Because its hosts are exceptionally resistant to culturing, this symbiont is best studied through advanced genomic approaches. To analyze the role of Xiphinematobacter sp. in its host, sequencing was performed on nematode communities, and then genomes were extracted for comparative genomics, gene ontology enrichment tests, polymorphism analysis, de Bruijn-based genome-wide association studies, and tests of pathway- and site-specific selection on genes predicted play a role in thethe important human gut-associated microbe Akkermansia muciniphila and many highly abundant free-living soil microbes. Like Akkermansia sp., Xiphinematobacter sp. is obligately associated with the gut of its hosts, which in this case consists of a group of plant-parasitic nematodes that are among the top 10 most destructive species to global agriculture, by vectoring plant viruses. This study examined the hypothesis that the key to this symbiont’s stable evolutionary association with its host is through provisioning nutrients that its host cannot make that may be lacking in the nematode’s plant phloem diet, such as essential amino acids and several vitamins. The significance of our research is in demonstrating, using population genomics, the signatures of selective pressure on these hypothesized roles to ultimately learn how this independently evolved symbiont functionally mirrors symbionts of phloem-feeding insects.Heme is an essential metabolite for most life on earth. Bacterial pathogens almost universally require iron to infect a host, often acquiring this nutrient in the form of heme. The Gram-negative pathogen Pseudomonas aeruginosa is no exception, where heme acquisition and metabolism are known to be crucial for both chronic and acute infections. To unveil unknown genes and pathways that could play a role with heme metabolic flux in this pathogen, we devised an omic-based approach we dubbed “Met-Seq,” for metabolite-coupled transposon sequencing. Met-Seq couples a biosensor with fluorescence-activated cell sorting (FACS) and massively parallel sequencing, allowing for direct identification of genes associated with metabolic changes. In this work, we first construct and validate a heme biosensor for use with P. aeruginosa and exploit Met-Seq to identify 188 genes that potentially influence intracellular heme levels. Identified genes largely consisted of metabolic pathways not previously associated with heme, inclup address this problem, which we dub “Met-Seq” (metabolite-coupled Tn sequencing). Met-Seq uses the powerful combination of fluorescent biosensors, fluorescence-activated cell sorting (FACS), and next-generation sequencing (NGS) to rapidly identify genes that influence the levels of specific intracellular metabolites. For proof of concept, we create and test a heme biosensor and then exploit Met-Seq to identify novel genes involved in the regulation of heme in the pathogen Pseudomonas aeruginosa Met-Seq-generated data were largely comprised of genes which have not previously been reported to influence heme levels in this pathogen, two of which we verify as novel heme-binding proteins. As heme is a required metabolite for host infection in P. aeruginosa and most other pathogens, our studies provide a new list of targets for potential antimicrobial therapies and shed additional light on the balance between infection, heme uptake, and heme biosynthesis.Oral lyophilized fecal microbiota transplantation (FMT) is effective in recurrent Clostridioides difficile infection (CDI); however, limited data exist on its efficacy in primary CDI and long-term microbial engraftment. Patients with primary or recurrent CDI were prospectively enrolled to receive oral FMT. Changes in the bacterial and fungal communities were characterized prior to and up to 6 months following treatment. A total of 37 patients with CDI (15 primary, 22 recurrent) were treated with 6 capsules each containing 0.35-g lyophilized stool extract. A total of 33 patients (89%) had sustained CDI cure, of whom 3 required a second course. There were no safety signals identified. FMT significantly increased bacterial diversity and shifted composition toward donor profiles in responders but not in nonresponders, with robust donor contribution observed to 6 months following FMT (P  less then  0.001). Responders showed consistent decreases in Enterobacteriaceae and increases in Faecalibacterium sp. Tomivosertib supplier to levels seen in donors.