Analysis of catRABC operon for catechol degradation from phenol-degrading Rhodococcus erythropolis

Appl Microbiol Biotechnol. 2007 Aug;76(1):159-68. doi: 10.1007/s00253-007-0997-6. Epub 2007 May 5.

Abstract

The gene cluster catRABC, involved in catechol degradation, was isolated from Rhodococcus erythropolis CCM2595. The genes catA, catB, catC, and the divergently transcribed catR code for catechol 1,2-dioxygenase, cis,cis-muconate cycloisomerase, muconolactone isomerase, and an IclR-type transcriptional regulator, respectively. Measurements of catechol 1,2-dioxygenase activity showed that the expression of catA is induced by phenol but not by catechol or cis,cis-muconate. The activity of catechol 1,2-dioxygenase was repressed by succinate, but no repression by glucose was observed. The transcription start points of catA and catR were determined by primer extension analysis, and the respective promoters (P-catA and P-catR) were thus localized. Measurements of promoter activity during batch cultivation using transcriptional fusion with the gfpuv reporter gene showed that expression of the catR-catABC operon is regulated at the level of transcription. Both P-catR and P-catA are repressed by CatR, and the induction of P-catA by phenol is maintained in the absence of the repressor (in R. erythropolis DeltacatR). Two different potential binding sites for the IclR-type regulator and a recognition site for the cyclic AMP receptor protein (CRP) were identified within the intergenic region between catR and catA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism
  • Base Sequence
  • Carbon-Carbon Double Bond Isomerases / genetics*
  • Carbon-Carbon Double Bond Isomerases / metabolism
  • Catechol 1,2-Dioxygenase / genetics*
  • Catechol 1,2-Dioxygenase / metabolism
  • Catechols / metabolism*
  • Cyclic AMP Receptor Protein / genetics
  • DNA, Intergenic / genetics
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • Genes, Bacterial*
  • Intramolecular Lyases / genetics*
  • Intramolecular Lyases / metabolism
  • Molecular Sequence Data
  • Multigene Family / genetics
  • Operon / genetics*
  • Phenol / metabolism*
  • Promoter Regions, Genetic*
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism
  • Rhodococcus / enzymology
  • Rhodococcus / genetics*
  • Sequence Alignment
  • Succinic Acid
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism
  • Transcription, Genetic*

Substances

  • Bacterial Proteins
  • Catechols
  • Cyclic AMP Receptor Protein
  • DNA, Intergenic
  • DNA-Binding Proteins
  • Repressor Proteins
  • Transcription Factors
  • CatR protein, bacteria
  • Phenol
  • Succinic Acid
  • Catechol 1,2-Dioxygenase
  • Carbon-Carbon Double Bond Isomerases
  • muconolactone delta-isomerase
  • Intramolecular Lyases
  • muconate cycloisomerase
  • catechol