Open AccessCharacterization of DegU, a response regulator in Listeria monocytogenes , involved in regulation of motility and contributes to virulence
Author(s) -
Knudsen Gitte M.,
Olsen John E.,
Dons Lone
Publication year - 2004
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1016/j.femsle.2004.09.039
Subject(s) - flagellin , virulence , biology , regulator , mutant , response regulator , listeria monocytogenes , gene product , regulator gene , microbiology and biotechnology , gene , bacillus subtilis , gene expression , genetics , bacteria
The degU ( lmo2515 ) gene encodes a putative response regulator in the food‐borne pathogen Listeria monocytogenes . It has 63% amino acid identity to the DegU response regulator of Bacillus subtilis . We have characterized the degU gene product in L. monocytogenes EGD by generation of a deletion mutant. The Δ degU mutant was found to be non‐motile in motility plate assay and no flagellin was detected. The mutant was attenuated in challenge of mice. Northern blot analysis suggested that the degU gene product is a transcriptional activator of the flagellin gene, flaA , at 25 °C. However, the degU gene product had no influence on the transcription of prfA encoding the major virulence regulator, PrfA. The results indicate that the putative DegU response regulator is a pleiotropic regulator involved in expression of both motility at low temperature and in vivo virulence in mice.