Open AccessGenetic Rearrangement Strategy for Optimizing the Dibenzothiophene Biodesulfurization Pathway in Rhodococcus erythropolis
Author(s) -
Guoqiang Li,
Shanshan Li,
Minglu Zhang,
Jun Wang,
Lin Zhu,
Liang Fang,
Rulin Liu,
Ma T
Publication year - 2008
Publication title -
applied and environmental microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.552
H-Index - 324
eISSN - 1070-6291
pISSN - 0099-2240
DOI - 10.1128/aem.02319-07
Subject(s) - dibenzothiophene , rhodococcus , rhodococcus rhodochrous , rhodococcus equi , computational biology , chemistry , biology , genetics , biochemistry , bacteria , gene , virulence , catalysis
Dibenzothiophene (DBT) and its derivatives can be microbially desulfurized by enzymes DszC, DszA, and DszB, which are encoded by the operondszABC and contribute to the conversion in tandem. We investigated the expression characteristics of thedsz operon. Our results revealed that the levels of transcription and translation ofdszA ,dszB , anddszC decreased according to the positions of the genes in thedsz operon. Furthermore, the translation ofdszB was repressed by an overlapping structure in thedsz operon. In order to get better and steady expression of the Dsz enzymes and optimize the metabolic flux of DBT, we rearranged thedsz operon according to the catalytic capabilities of the Dsz enzymes and expressed the rearrangeddsz operon,dszBCA , inRhodococcus erythropolis . After rearrangement, the ratio ofdszA ,dszB , anddszC mRNAs in the cells was changed, from 11:3.3:1 to 1:16:5. Western blot analysis revealed that the levels of expression ofdszB anddszC had been enhanced but that the expression ofdszA had decreased. The desulfurization activity of resting cells prepared fromR. erythropolis DRB, which carried the rearrangeddsz operon, was about 12-fold higher than that of resting cells ofR. erythropolis DRA, which carried the original operon in a similarly constructed vector.