|A novel redox-sensing transcriptional regulator CyeR controls expression
of an old yellow enzyme family protein in Corynebacterium glutamicum.
Microbiology 156: 1335-1341. 2010.
S. Ehira, H. Teramoto, M. Inui and H. Yukawa.
Corynebacterium glutamicum cgR_2930 (cyeR) encodes a transcriptional regulator of the ArsR family. Its gene product,
CyeR, was shown here to repress the expression of cyeR and the cgR_2931 (cye1)-cgR_2932 operon, which is located upstream of cyeR in the opposite orientation. The cye1 gene encodes an Old Yellow Enzyme family protein, members of which have been implicated in the oxidative stress response. CyeR binds to the intergenic region between cyeR and cye1. Expression of cyeR and cye1 is induced by oxidative stress, and the DNA-binding activity of CyeR is
impaired by oxidants such as diamide and H(2)O(2). CyeR contains two cysteine
residues, Cys-36 and Cys-43. Whereas mutation of the former (C36A) has
no effect on the redox regulation of CyeR activity, mutating the latter
(C43A, C43S) abolishes the DNA-binding activity of CyeR. Cys-43 of CyeR
and its C36A derivative are modified upon treatment with diamide, suggesting
an important role for Cys-43 in the redox regulation of CyeR activity.
It is concluded that CyeR is a redox-sensing transcriptional regulator
that controls cye1 expression.