Project description:Antibiotic use can lead to expansion of multi-drug resistant pathobionts within the gut microbiome that can cause life-threatening infections. Selective alternatives to conventional antibiotics are in dire need. Here, we describe a Klebsiella PhageBank that enables the rapid design of antimicrobial bacteriophage cocktails to treat multi-drug resistant Klebsiella pneumoniae. Using a transposon library in carbapenem-resistant K. pneumoniae, we identified host factors required for phage infection in major Klebsiella phage families. Leveraging the diversity of the PhageBank and experimental evolution strategies, we formulated combinations of phages that minimize the occurrence of phage resistance in vitro. Optimized bacteriophage cocktails selectively suppressed the burden of multi-drug resistant K. pneumoniae in the mouse gut microbiome and drove bacterial populations to lose key virulence factors that act as phage receptors. Further, phage-mediated diversification of bacterial populations in the gut enabled co-evolution of phage variants with higher virulence and a broader host range. Altogether, the Klebsiella PhageBank represents a roadmap for both phage researchers and clinicians to enable phage therapy against a critical multidrug-resistant human pathogen.
Project description:The present work describes LC-ESI-MS/MS analyses of tryptic digestion peptides from phages that infect Staphylococcus aureus-causing mastitis, and isolated from dairy products. A total of 1935 non-redundant peptides belonging to 1282 proteins were identified and analyzed. Among them, 80 staphylococcal peptides from phages were confirmed. These peptides belong to proteins such as phage repressors, structural phage proteins, uncharacterized phage proteins and complement inhibitors. Moreover, of the phage origin peptides found, eighteen of them were specific to S. aureus strains. These diagnostic peptides could be useful for the identification and characterization of S. aureus strains that cause mastitis. Furthermore, a study of bacteriophage phylogeny and the relationship among the identified phage peptides and the bacteria they infect was also performed. The results show the specific peptides which are present in closely related phages, and the existing links between bacteriophage phylogeny and the respective Staphylococcus spp. infected.
2021-03-25 | PXD023530 | Pride
Project description:Phages that infect Enterobacteriales
| PRJNA592009 | ENA
Project description:Phages that infect Erwinia amylovora
Project description:Klebsiella pneumoniae has risen to prominence as a major threat to human health, with hypervirulent and drug-resistant lineages spreading globally. Given their antimicrobial resistant phenotypes, new therapies are required for the treatment of these infections, and bacteriophages (phages) that kill Klebsiella are being identified for use in phage therapy. In order to circumvent the evolution of phage-resistance taking hold the way that drug-resistance has, clear and considered actions are needed in selecting the phages that would be used in therapeutic cocktails. It is known that annotation of phage genomes is poor, potentially obscuring those phages with the most therapeutic potential. Here we show that phages isolated from infrequently sampled environments have features of therapeutic potential and developed a computational tool called STEP3 to understand the evolutionary features that distinguish the component parts of diverse phages, features that proved particularly suitable to detection of virion proteins with only distantly related homologies. These features were integrated into an ensemble framework to achieve a stable and robust prediction performance by STEP3. Proteomics-based analysis of two phages validated the prediction accuracy of STEP3 and revealed the virions contain component parts that include DNA-binding factors, otherwise unrecognizable capsule degradation enzymes and membrane translocation factors.
Project description:Diminished colonic health is associated with various age-related pathologies. In this study, we applied an integrative approach to reveal potential interactions between determinants of colonic health in aging C57BL/6J mice. Analysis of gut microbiota composition revealed an enrichment of various potential pathobionts, including Desulfovibrio spp., and a decline of the health-promoting Akkermansia spp. and Lactobacillus spp. during aging. Intraluminal concentrations of various metabolites varied between ages and we found evidence for an increased gut permeability at higher age. Colonic gene expression analysis suggested that during the early phase of aging (between 6 and 12 months), expression of genes involved in epithelial-to-mesenchymal transition and (re)organization of the extracellular matrix were increased. Differential expression of these genes was strongly correlated with Bifidobacterium spp. During the later phase of aging (between 12 and 28 months), gene expression profiles pointed towards a diminished antimicrobial defense and were correlated with an uncultured Gastranaerophilales spp. This study demonstrates that aging is associated with pronounced changes in gut microbiota composition and colonic gene expression. Furthermore, the strong correlations between specific bacterial genera and host gene expression may imply that orchestrated interactions take place in the vicinity of the colonic wall and potentially mediate colonic health during aging.
2018-05-09 | GSE113257 | GEO
Project description:Phages that infect Escherichia coli K-12 MG1655
Project description:Pseudomonas virus PA5oct has a large, linear, double-stranded DNA genome (286,783 bp) and is related to Escherichia phages 121Q/PBECO 4, Klebsiella phage vB_KleM-RaK2, Klebsiella phage K64-1, and Cronobacter phage vB_CsaM_GAP32. A protein-sharing network analysis highlights the conserved core genes within this clade. Combining hybrid genome sequencing, RNA-Seq and mass spectrometry analyses of its virion proteins allowed us to accurately identify genes and elucidate regulatory elements for this phage (ncRNAs, tRNAs and promoter elements). In total PA5oct encodes 449 CDS of which 93, have been identified as virion-associated based on ESI-MS/MS. The RNA-Seq-based temporal genome organization suggests a gradual take-over by viral transcripts from 21%, 69%, and 93% at 5, 15 and 25 min after infection, respectively . Like many large phages, PA5oct is not organized into contiguous regions of temporal transcription. However, although the temporal regulation of the PA5oct genome expression reveals specific genome clusters expressed in early and late infection, many genes encoding experimentally observed structural proteins surprisingly appear to remain almost untranscribed throughout the infection cycle. Within the host, operons associated with elements of a cryptic Pf1-like prophage are upregulated, as are operons responsible for Psl exopolysaccharide (pslE-J) and periplasmic nitrate reductase (napA-F) production. The characterization described here represents a crucial step towards understanding the genomic complexity as well as molecular diversity of jumbo viruses.
Project description:There is significant interest in altering the course of cardiometabolic disease development via the gut microbiome. Nevertheless, the highly abundant phage members of the complex gut ecosystem -which impact gut bacteria- remain understudied. Here, we characterized gut virome changes associated with metabolic syndrome (MetS), a highly prevalent clinical condition preceding cardiometabolic disease, in 196 participants with a combination of whole genome shotgun and virus
like particle sequencing. MetS gut virome populations exhibited decreased richness and diversity, but larger inter-individual variation. These populations were enriched in phages infecting Bacteroidaceae and depleted in those infecting Ruminococcaeae. Differential abundance analysis identified eighteen viral clusters (VCs) as significantly associated with either MetS or healthy viromes. Among these are a MetS-associated Roseburia VC that is related to healthy control-associated Faecalibacterium and Oscillibacter VCs. Further analysis of these VCs revealed the Candidatus Heliusviridae, a highly widespread gut phage lineage found in 90+% of the participants. The identification of the temperate Ca. Heliusviridae provides a novel starting point to a better understanding of the effect that phages have on their bacterial hosts and the role that this plays in MetS