Functional analysis of sigH expression in Corynebacterium glutamicum.
The sigH gene of Corynebacterium glutamicum encodes ECF sigma factor sigmaH. The gene apparently plays an important role in other stress responses as well as heat stress response. In this study, we found that deleting the sigH gene made C. glutamicum cells sensitive to the thiol-specific oxidant diamide. In the sigH mutant strain, the activity of thioredoxin reductase markedly decreased, suggesting that the trxB gene encoding thioredoxin reductase is probably under the control of sigmaH. The expression of sigH was stimulated in the stationary growth phase and modulated by diamide. In addition, the SigH protein was required for the expression of its own gene. These data indicate that the sigH gene of C. glutamicum stimulates and regulates its own expression in the stationary growth phase in response to environmental stimuli, and participates in the expression of other genes which are important for survival following heat and oxidative stress response.
Kim
Tae-Hyun
TH
Graduate School of Biotechnology, Korea University, Anam-Dong, Sungbuk-Ku, Seoul 136-701, Republic of Korea.
Kim
Hyung-Joon
HJ
Park
Joon-Sung
JS
Kim
Younhee
Y
Kim
Pil
P
Lee
Heung-Shick
HS
D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D048230:Corynebacterium glutamicum / Q000235:genetics*; D017931:DNA Primers; D003958:Diamide / Q000494:pharmacology; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D005798:Genes, Bacterial; D018384:Oxidative Stress; D012808:Sigma Factor / Q000235:genetics*
D001426:Bacterial Proteins; D017931:DNA Primers; C120328:SigH protein, bacteria; D012808:Sigma Factor; D003958:Diamide