LuxS/autoinducer-2 quorum sensing molecule regulates transcriptional virulence gene expression in Clostridium difficile.
Toxigenic Clostridium difficile CCUG19126 produces the autoinducer-2 (AI-2) quorum sensing molecule that induces bioluminescence in Vibrio harveyi BB170 reporter strain. AI-2-containing cell-free supernatants from mid-log phase C. difficile and Escherichia coli DH5alpha expressing recombinant luxS(cd) upregulated the transcript levels of tcdA (7-10-fold), tcdB (4-6-fold), and tcdE (2-3-fold) in early-log C. difficile. In contrast, no induction occurred when cells were exposed to sterile medium or to cell-free supernatant from E. coli DH5alpha. AI-2 did not significantly increase the level of toxin A in early-log C. difficile. These results suggest that LuxS(cd)-dependent signaling regulates virulence gene expression at the transcriptional level in C. difficile.
Lee
Alex Sek Yew
AS
Microbial Pathogenesis Laboratory, Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
Song
Keang Peng
KP
D001426:Bacterial Proteins / Q000502:physiology*; D001483:Base Sequence; D013437:Carbon-Sulfur Lyases; D003001:Cloning, Molecular; D016360:Clostridioides difficile / Q000235:genetics / Q000472:pathogenicity*; D017931:DNA Primers; D004269:DNA, Bacterial; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology*; D005798:Genes, Bacterial; D005816:Genetic Complementation Test; D008969:Molecular Sequence Data; D014158:Transcription, Genetic / Q000502:physiology*; D014774:Virulence / Q000235:genetics*
D001426:Bacterial Proteins; D017931:DNA Primers; D004269:DNA, Bacterial; D013437:Carbon-Sulfur Lyases; C117753:LuxS protein, Bacteria