Transcriptional regulation of styrene degradation in Pseudomonas putida CA-3.
The styrene degradative pathway in Pseudmonas putida CA-3 has previously been shown to be divided into an upper pathway involving the conversion of styrene to phenylacetic acid and a lower pathway for the subsequent degradation of phenylacetic acid. It is reported here that expression of the regulatory genes styS and styR is essential for transcription of the upper pathway, but not for degradation of the lower pathway inducer, phenylacetic acid. The presence of phenylacetic acid in the growth medium completely repressed the upper pathway enzymes even in the presence of styrene, the upper pathway inducer. This repression is mediated at the transcription level by preventing expression of the styS and styR regulatory genes. Finally, an examination was made of the various stages of the diauxic growth curve obtained when P. putida CA-3 was grown on styrene together with an additional carbon source and it is reported that catabolite repression may involve a different mechanism to transcriptional repression by an additional carbon source.
Microbiology Department, National University of Ireland, Cork, Ireland1.
Niall D
ND
O'Leary
Department of Industrial Microbiology, National University of Ireland, Dublin, Ireland2.
Kevin E
KE
O'Connor
Institut für Biotechnologie, ETH Hönggerberg, CH-8093 Zurich, Switzerland3.
Wouter
W
Duetz
Microbiology Department, National University of Ireland, Cork, Ireland1.
Alan D W
ADW
Dobson
D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001673:Biodegradation, Environmental; D002851:Chromatography, High Pressure Liquid; D015964:Gene Expression Regulation, Bacterial; D000071677:Histidine Kinase; D010648:Phenylacetates / Q000378:metabolism*; D011494:Protein Kinases / Q000235:genetics* / Q000378:metabolism; D016958:Pseudomonas putida / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D012329:RNA, Bacterial / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D020058:Styrene / Q000378:metabolism*
D001426:Bacterial Proteins; D010648:Phenylacetates; D012329:RNA, Bacterial; D012333:RNA, Messenger; C110964:StyR protein, Pseudomonas; D020058:Styrene; D011494:Protein Kinases; D000071677:Histidine Kinase; C025136:phenylacetic acid