CRP-Cyclic AMP Regulates the Expression of Type 3 Fimbriae via Cyclic di-GMP in Klebsiella pneumoniae.

ABSTRACT: Klebsiella pneumoniae is the predominant pathogen isolated from liver abscesses of diabetic patients in Asian countries. However, the effects of elevated blood glucose levels on the virulence of this pathogen remain largely unknown. Type 3 fimbriae, encoded by the mrkABCDF genes, are important virulence factors in K. pneumoniae pathogenesis. In this study, the effects of exogenous glucose and the intracellular cyclic AMP (cAMP) signaling pathway on type 3 fimbriae expression regulation were investigated. The production of MrkA, the major subunit of type 3 fimbriae, was increased in glucose-rich medium, whereas cAMP supplementation reversed the effect. MrkA production was markedly increased by cyaA or crp deletion, but slightly decreased by cpdA deletion. In addition, the mRNA levels of mrk

SUBMITTER: Lin CT 

PROVIDER: S-EPMC5025149 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature