TY - JOUR
T1 - Regulation of superoxide stress in Pseudomonas putida KT2440 is different from the SoxR paradigm in Escherichia coli
AU - Park, Woojun
AU - Peña-Llopis, Samuel
AU - Lee, Yunho
AU - Demple, Bruce
N1 - Funding Information:
S.P.-L. was supported by a postdoctoral fellowship from the Valencian Government (Generalitat Valenciana) in Spain. This work was supported by NCI, National Institutes of Health Grant CA37831 to B.D. and a NCRC (National Core Research Center) Grant (R15-2003-002-01002-0), a grant (R0503441) from BioGreen21 program, Rural Development Administration, and Ministry of Education and Human Resource Development (Grant R0508751), Republic of Korea to W.P.
PY - 2006/3/3
Y1 - 2006/3/3
N2 - In Escherichia coli, the SoxR regulon orchestrates genes for defense against certain types of oxidative stress through the SoxR-regulated synthesis of the SoxS transcription activator. The Pseudomonas putida genome did not reveal a clear soxS homolog. The P. putida SoxR protein appears to be functional: its expression in an E. coli ΔsoxR strain restored the paraquat inducibility of soxS. Of nine candidate P. putida oxidative stress genes, which are known to be SoxR regulon in E. coli, tested for response to superoxide or nitric oxide, fumC-1, sodA, zwf-1, and particularly fpr, encoding ferredoxin:NADP+ reductase, were induced, all independent of P. putida soxR. Disruption of the fpr and finR, a regulatory protein that is required for paraquat-dependent expression of the fpr, resulted in more oxidative stress sensitivity. However, a P. putida soxR-deletion strain had normal resistance to the superoxide-generating agent paraquat. The data presented here show that the genetic responses to superoxide stress in P. putida differ markedly from those seen in E. coli and Salmonella, and the role of P. putida soxR remains to be established.
AB - In Escherichia coli, the SoxR regulon orchestrates genes for defense against certain types of oxidative stress through the SoxR-regulated synthesis of the SoxS transcription activator. The Pseudomonas putida genome did not reveal a clear soxS homolog. The P. putida SoxR protein appears to be functional: its expression in an E. coli ΔsoxR strain restored the paraquat inducibility of soxS. Of nine candidate P. putida oxidative stress genes, which are known to be SoxR regulon in E. coli, tested for response to superoxide or nitric oxide, fumC-1, sodA, zwf-1, and particularly fpr, encoding ferredoxin:NADP+ reductase, were induced, all independent of P. putida soxR. Disruption of the fpr and finR, a regulatory protein that is required for paraquat-dependent expression of the fpr, resulted in more oxidative stress sensitivity. However, a P. putida soxR-deletion strain had normal resistance to the superoxide-generating agent paraquat. The data presented here show that the genetic responses to superoxide stress in P. putida differ markedly from those seen in E. coli and Salmonella, and the role of P. putida soxR remains to be established.
KW - Biodegradation
KW - Ferredoxin reductase
KW - LysR-type transcriptional factor
KW - Nitric oxide
KW - Oxidative stress
KW - Paraquat
UR - http://www.scopus.com/inward/record.url?scp=30944437009&partnerID=8YFLogxK
U2 - 10.1016/j.bbrc.2005.12.142
DO - 10.1016/j.bbrc.2005.12.142
M3 - Article
C2 - 16412384
AN - SCOPUS:30944437009
SN - 0006-291X
VL - 341
SP - 51
EP - 56
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 1
ER -