title: Identification and characterization of KvgAS, a two-component system in Klebsiella pneumoniae CG43.
abstract: A two-component system encoding gene cluster kvgAS that is present only in virulent Klebsiella pneumoniae CG43 was isolated and its sequence determined. RT-PCR and Southern analysis demonstrated that kvgAS is organized as an operon. No apparent effect of a kvgS deletion on bacterial virulence was observed in a mouse peritonitis model. In the presence of paraquat or 2,2-dipyridyl, the activity of kvgAS promoter in the kvgS mutant was found to be reduced to half of the level in the wild-type strain. The data suggest that the KvgAS system is autoregulated and plays a role in countering free radical stresses and sensing iron-limiting conditions.
authors.affiliation: Department of Life Science and Institute of Molecular Medicine, National Tsing Hua University, Hsin Chu, Taiwan.
authors.forename: Yi-Chyi
authors.initials: YC
authors.lastname: Lai
authors.forename: Ging-Ting
authors.initials: GT
authors.lastname: Lin
authors.forename: Shu-Li
authors.initials: SL
authors.lastname: Yang
authors.forename: Hwan-You
authors.initials: HY
authors.lastname: Chang
authors.forename: Hwei-Ling
authors.initials: HL
authors.lastname: Peng
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics*; D003001:Cloning, Molecular; D017353:Gene Deletion; D015964:Gene Expression Regulation, Bacterial; D000071677:Histidine Kinase; D007710:Klebsiella Infections / Q000382:microbiology*; D007711:Klebsiella pneumoniae / Q000235:genetics* / Q000472:pathogenicity*; D051379:Mice; D005810:Multigene Family / Q000235:genetics; D016296:Mutagenesis; D010538:Peritonitis / Q000382:microbiology; D011494:Protein Kinases / Q000235:genetics; D017422:Sequence Analysis, DNA; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D011494:Protein Kinases; D000071677:Histidine Kinase