Benzoate catabolite repression of the phenol degradation in Acinetobacter calcoaceticus PHEA-2.
Acinetobacter calcoaceticus PHEA-2 exhibited a delayed utilization of phenol in the presence of benzoate. Benzoate supplementation completely inhibited phenol degradation in a benzoate 1,2-dioxygenase knockout mutant. The mphR encoding the transcriptional activator and mphN encoding the largest subunit of multi-component phenol hydroxylase in the benA mutant were significantly downregulated (about 7- and 70-fold) on the basis of mRNA levels when benzoate was added to the medium. The co-transformant assay of E. coli JM109 with mphK::lacZ fusion and the plasmid pETR carrying mphR gene showed that MphR did not activate the mph promoter in the presence of benzoate. These results suggest that catabolite repression of phenol degradation by benzoate in A. calcoaceticus PHEA-2 is mediated by the inhibition of the activator protein MphR.
Zhan
Yuhua
Y
College of Biological Sciences, China Agriculture University, Beijing, PR China.
Yu
Haiying
H
Yan
Yongliang
Y
Ping
Shuzhen
S
Lu
Wei
W
Zhang
Wei
W
Chen
Ming
M
Lin
Min
M
D016954:Acinetobacter calcoaceticus / Q000502:physiology*; D019677:Artificial Gene Fusion; D001565:Benzoates / Q000378:metabolism*; D015536:Down-Regulation; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D015971:Gene Expression Regulation, Enzymologic; D055786:Gene Knockout Techniques; D017930:Genes, Reporter; D006899:Mixed Function Oxygenases / Q000096:biosynthesis; D010105:Oxygenases / Q000235:genetics; D019800:Phenol / Q000378:metabolism*; D010957:Plasmids; D014157:Transcription Factors / Q000096:biosynthesis; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
D001565:Benzoates; D014157:Transcription Factors; D019800:Phenol; D006899:Mixed Function Oxygenases; D010105:Oxygenases; C019766:benzoate 1,2-dioxygenase; C022336:phenol 2-monooxygenase; D001616:beta-Galactosidase