Project description:Klebsiella pneumoniae is an arising threat to human health. However, host immune responses in response to this bacterium remain to be elucidated. The goal of this study was to identify the dominant host immune responses associated with Klebsiella pneumoniae pulmonary infection. Pulmonary mRNA profiles of 6-8-weeks-old BALB/c mice infected with/without Klebsiella pneumoniae were generated by deep sequencing using Illumina Novaseq 6000. qRT–PCR validation was performed using SYBR Green assays. Using KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis, we identified several immune associated pathways, including complement and coagulation cascades, Toll-like receptor signaling pathway, Rap1 signaling pathway, chemokine signaling pathway, TNF signaling pathway, phagosome and NOD-like receptor signaling pathway, were involved in Klebsiella pneumoniae pulmonary infection. Using ICEPOP (Immune CEll POPulation) analysis, we found that several cell types were involved in the host immune response to Klebsiella pneumoniae pulmonary infection, including dendritic cells, macrophages, monocytes, NK (natural killer) cells, stromal cells. Further, IL-17 chemokines were significantly increased during Klebsiella pneumoniae infection. This study provided evidence for further studying the pathogenic mechanism of Klebsiella pneumoniae pneumonia infection.
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:Klebsiella pneumoniae belongs to the group of bacterial pathogens causing the majority of antibiotic-resistant nosocomial infections worldwide; however, the molecular mechanisms underlying post-translational regulation of its physiology are poorly understood. Here we perform a comprehensive analysis of Klebsiella phosphoproteome, focusing on HipA, a Ser/Thr kinase involved in antibiotic tolerance in Escherichia coli. We show that overproduced K. pneumoniae HipA (HipAkp) is toxic to both E. coli and K. pneumoniae and its toxicity can be rescued by overproduction of the antitoxin HipBkp. Importantly, HipAkp overproduction leads to increased tolerance against ciprofloxacin, a commonly used antibiotic in the treatment of K. pneumoniae infections. Proteome and phosphoproteome analyses in the absence and presence of ciprofloxacin confirm that HipAkp has Ser/Thr kinase activity, auto-phosphorylates at S150, and shares multiple substrates with HipAec, thereby providing a valuable resource to clarify the molecular basis of tolerance and the role of Ser/Thr phosphorylation in this human pathogen.
Project description:Klebsiella pneumoniae is a bacterial pathogen that causes nosocomial infection in humans and is acquiring antibiotic resistance at an alarming rate. This study investigates the effect of zinc limitation on the phosphoproteome of K. pneumoniae using quantitative mass spectrometry to provide insight into the cell signaling methods used to respond to nutrient limited conditions like those experienced when colonizing a host.
Project description:Klebsiella pneumoniae poses a significant global health threat primarily attributable to its pronounced resistance. Here, we report an in vitro acquired resistance analyses of K. pneumoniae to the combination of amikacin and polymyxin B. We found some differentially expressed genes associated with the resistome of K. pneumoniae. The main differences were found in the genes aphA, asmA, phoP, and in the arn operon. Once these genes are related to modification in lipopolysaccharides, aminoglycosides and in the membrane structure, the mechanisms associated with them can justify the resistance acquisition to amikacin and polymyxin b.
