title: Functional characterization of a novel Mn2+ dependent protein serine/threonine kinase KpnK, produced by Klebsiella pneumoniae strain MGH78578.
abstract: Klebsiella pneumoniae MGH78578 contains ~500 uncharacterized signaling proteins and in this study, we characterized the biological functions of a novel eukaryotic-like serine/threonine kinase; ESTK (KpnK). Studies demonstrated that KpnK undergoes autophosphorylation within the pH range 7.0-7.5 at 37°C in a time- and concentration- dependent manner, with Mn(2+) as its cofactor. The ΔkpnK mutant exhibited higher sensitivity to gastrointestinal and oxidative stresses. Deletion of kpnK resulted in a two to threefold increased susceptibility towards imipenem, cefepime, ceftriaxone and ceftazidime. Our study has provided overall evidence for the involvement of ESTK in regulating bacterial physiology, stress response and drug resistance. This report has unmasked the occurrence of Ser/Thr kinase mediated signaling for the first time in K. pneumoniae.
authors.affiliation: Council of Scientific Industrial Research (CSIR), Institute of Microbial Technology, Bacterial Signaling and Drug Resistance Laboratory, Chandigarh 160036, India.
authors.forename: Vijaya Bharathi
authors.initials: VB
authors.lastname: Srinivasan
authors.forename: Vasanth
authors.initials: V
authors.lastname: Vaidyanathan
authors.forename: Amitabha
authors.initials: A
authors.lastname: Mondal
authors.forename: Manjunath
authors.initials: M
authors.lastname: Venkataramaiah
authors.forename: Govindan
authors.initials: G
authors.lastname: Rajamohan
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D002413:Cations, Divalent; D002511:Cephalosporins / Q000494:pharmacology; D003067:Coenzymes / Q000737:chemistry / Q000378:metabolism; D024901:Drug Resistance, Multiple, Bacterial / Q000502:physiology*; D004926:Escherichia coli; D017353:Gene Deletion; D015870:Gene Expression; D006863:Hydrogen-Ion Concentration; D015378:Imipenem / Q000494:pharmacology; D007711:Klebsiella pneumoniae / Q000737:chemistry / Q000187:drug effects / Q000502:physiology*; D008345:Manganese / Q000378:metabolism*; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D013312:Stress, Physiological / Q000502:physiology
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002413:Cations, Divalent; D002511:Cephalosporins; D003067:Coenzymes; D011994:Recombinant Proteins; D008345:Manganese; D015378:Imipenem; D017346:Protein Serine-Threonine Kinases