Project description:Hypervirulent Klebsiella pneumoniae (hvKp) causes invasive infections and severe systemic inflammation. In this study, outer membrane vesicles (OMVs) derived from clinically isolated hvKp and classical K. pneumoniae (cKp) strains were characterized using an integrated proteogenomic workflow combining whole-genome sequencing and label-free LC–MS/MS proteomics. The dataset includes quantitative proteomic profiles of OMVs and whole-cell lysates together with strain-specific protein annotations for comparative analyses of OMVs cargo composition, functional annotation, and pathogenicity.
Project description:This study investigates multidrug-resistant Klebsiella pneumoniae KP21-10C using whole genome sequencing and targeted energy metabolomics. Genomic sequencing data were generated to characterize the bacterial genome, and targeted LC-MS/MS metabolomics was performed to quantify energy metabolism-related metabolites under doxycycline monotherapy and cepharanthine hydrochloride plus doxycycline combination treatment.
Project description:With increasingly concerning strains of antimicrobial resistant strains of the commensal, gram-negative bacteria Klebsiella pneumoniae emerging, there is a pressing need to better understand the pathogen and mechanisms behind its pathogenicity. This study investigated the regulatory mechanisms in strain MGH 78578 of two major sigma factors, the house-keeping sigma factor RpoD, and the general stress response sigma factor RpoS, in mid-exponential and early stationary phase using chromatin immunoprecipitation with exonuclease treatment (ChIP-exo) followed by deep sequencing. Combining ChIP-exo and transcriptome analysis allowed for the determination of sigma factor binding sites, binding motifs, and genes included in the phase-specific sigmulons. The number of genes included in the RpoS sigmulon was greater than in the RpoD sigmulon, with 1,833 and 1,690 genes included, respectively; however, a majority of sigmulon genes were found in all phase-specific sigmulons. Focussing on pathogenicity genes, 20 antimicrobial resistance genes (ARGs) and 155 virulence genes, only two ARGs were found exclusively in one phase-specific sigmulon, an oxacillin-hydrolysing class D beta-lactamase and chloramphenicol efflux MFS transporter CmlA5, which were found in the RpoD sigmulon in early stationary phase. Notably, six unnamed proteins that are or pertain to fimbrial proteins were found uniquely in the RpoS sigmulon in early stationary phase. From this, it can be hypothesised that early stationary phase might be an important phase for pathogenicity gene regulation. While there is little conservation in RpoS sigmulons from strain to strain, RpoS appears to have a consistent overarching role across strains, including a role as a regulator of pathogenicity genes.
