Premium
Differential gene expression in response to phenol and catechol reveals different metabolic activities for the degradation of aromatic compounds in Bacillus subtilis
Author(s) -
Tam Le Thi,
Eymann Christine,
Albrecht Dirk,
Sietmann Rabea,
Schauer Frieder,
Hecker Michael,
Antelmann Haike
Publication year - 2006
Publication title -
environmental microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.954
H-Index - 188
eISSN - 1462-2920
pISSN - 1462-2912
DOI - 10.1111/j.1462-2920.2006.01034.x
Subject(s) - regulon , operon , derepression , bacillus subtilis , catabolite repression , biology , biochemistry , catechol , heat shock , sigma factor , heat shock protein , gene , regulation of gene expression , bacteria , gene expression , genetics , promoter , escherichia coli , mutant , psychological repression
Summary Aromatic organic compounds that are present in the environment can have toxic effects or provide carbon sources for bacteria. We report here the global response of Bacillus subtilis 168 to phenol and catechol using proteome and transcriptome analyses. Phenol induced the HrcA, σ B and CtsR heat‐shock regulons as well as the Spx disulfide stress regulon. Catechol caused the activation of the HrcA and CtsR heat‐shock regulons and a thiol‐specific oxidative stress response involving the Spx, PerR and FurR regulons but no induction of the σ B regulon. The most surprising result was that several catabolite‐controlled genes are derepressed by catechol, even if glucose is taken up under these conditions. This derepression of the carbon catabolite control was dependent on the glucose concentration in the medium, as glucose excess increased the derepression of the CcpA‐dependent lichenin utilization licBCAH operon and the ribose metabolism rbsRKDACB operon by catechol. Growth and viability experiments with catechol as sole carbon source suggested that B. subtilis is not able to utilize catechol as a carbon‐energy source. In addition, the microarray results revealed the very strong induction of the yfiDE operon by catechol of which the yfiE gene shares similarities to glyoxalases/bleomycin resistance proteins/extradiol dioxygenases. Using recombinant His 6 ‐YfiE Bs we demonstrate that YfiE shows catechol‐2,3‐dioxygenase activity in the presence of catechol as the metabolite 2‐hydroxymuconic semialdehyde was measured. Furthermore, both genes of the yfiDE operon are essential for the growth and viability of B. subtilis in the presence of catechol. Thus, our studies revealed that the catechol‐2,3‐dioxygenase YfiE is the key enzyme of a meta cleavage pathway in B. subtilis involved in the catabolism of catechol.