Lysine decarboxylase expression by Vibrio vulnificus is induced by SoxR in response to superoxide stress.
Lysine decarboxylase expression by Vibrio vulnificus, which is up-regulated by CadC in response to acid stress, is also induced by SoxR in response to superoxide stress. SoxR binds to the promoter region of the cadBA operon, coding for a lysine-cadaverine antiporter (CadB) and a lysine decarboxylase (CadA). The induction of cadBA transcription by SoxR is independent of CadC. Cadaverine, which neutralizes the external medium, also appears to scavenge superoxide radicals, since increasing cellular cadaverine by elevating the gene dosage of cadBA significantly diminished the induction of Mn-containing superoxide dismutase under methyl viologen-induced oxidative stress. Consistently, a lack of cadaverine caused by mutation in cadA resulted in low tolerance to oxidative stress compared with that of the wild type.
Kim
Ju-Sim
JS
Department of Life Science and Interdisciplinary Program of Integrated Biotechnology, Sogang University, Seoul 121-742, Korea.
Choi
Sang Ho
SH
Lee
Jeong K
JK
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002103:Cadaverine / Q000378:metabolism; D002262:Carboxy-Lyases / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D018869:Heat-Shock Response; D006863:Hydrogen-Ion Concentration; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism / Q000494:pharmacology*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D041261:Vibrio vulnificus / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development / Q000502:physiology
D001426:Bacterial Proteins; C080050:CadC protein, Bacteria; D012097:Repressor Proteins; D014157:Transcription Factors; D013481:Superoxides; C070724:SoxR protein, Bacteria; D002262:Carboxy-Lyases; C021520:lysine decarboxylase; D002103:Cadaverine