Project description:Complete Genome Sequences of Three Pseudomonas aeruginosa Phages of the Genus Phikmvvirus, vB_Pae4841-AFR43, vB_Pae10145-KEN1 and vB_Pae9718-KEN10
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:To investigate the whole-genome gene expression difference between the wild-type and capsule deletion mutant in Klebsiella pneumoniae MGH 78578. The mutants analyzed in this study are further described in Huang T.W., Stapleton J.C., Chang H.Y., Tsai S.F., Palsson B.O., Charusanti P. Capsule removal via lambda-Red knockout system perturbs biofilm formation and fimbriae extression in Klesiella pneumoniae MGH 78578 (manuscript submission) A six chip study using total RNA recovered from three separate wild-type cultures and three separate cultures of a capsule deltion mutant of Klebsiella pneumoniae MGH 78578. The capsule gene cluster (KPN_02493 to KPN_02515) was entirely removed in the capsule deletion mutant. Each chip measures the expression level of 5,305 genes from Klebsiella pneumoniae MGH 78578 and the associated five plasmids (pKPN3, pKPN4, pKPN5, pKPN6 and pKPN7) with 50-mer oligo tiling array with 30-mer spacer.
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.