Open AccessThe Brevibacterium flavum sigma factor SigB has a role in the environmental stress response
Author(s) -
Halgasova Nora,
Bukovska Gabriela,
Ugorcakova Jana,
Timko Jozef,
Kormanec Jan
Publication year - 2002
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 - 10.1111/j.1574-6968.2002.tb11418.x
Subject(s) - sigma factor , mutant , biology , gene , genetics , wild type , mutation , microbiology and biotechnology , gene expression , promoter
We have previously cloned a gene encoding a SigB, a principal‐like sigma factor in Brevibacterium flavum , which was induced by several stress conditions. To clarify the in vivo function of this sigma factor, the sigB gene was disrupted by a homologous recombination, replacing the internal essential coding region in B. flavum chromosome by a kanamycin resistance marker gene. This mutation dramatically decreased vegetative growth rates of B. flavum . Studies of the effect of the sigB mutation on growth and viability of the cells under conditions of stress showed that the sigB mutant had increased susceptibility to acid, salt, alcohol, heat and cold stress. The plasmid‐born wild‐type sigB gene complemented the mutation. Based on the results, we propose that SigB has a role in vegetative growth and in response to various environmental stresses.