Novel approach to the improvement of biphenyl and polychlorinated biphenyl degradation activity: promoter implantation by homologous recombination.

Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
Applied and Environmental Microbiology (Impact Factor: 3.95). 02/2003; 69(1):146-53. DOI: 10.1128/AEM.69.1.146-153.2003
Source: PubMed

ABSTRACT To improve the capabilities of microorganisms relevant for biodegradation, we developed a new genetic approach and applied it to the bph operon (bphEGF[orf4]A1A2A3CD[orf1]A4R) of Pseudomonas sp. strain KKS102 to enhance its biphenyl- and polychlorinated biphenyl (PCB)-degrading activity. A native promoter of the bph operon, which was under control, was replaced through homologous recombination by a series of promoters that had constitutive activity. By testing a series of promoters with various strengths, we were able to obtain strains that have enhanced degradation activity for biphenyl and PCBs. This strategy removes the rate-limiting factor associated with transcription and has the potential to improve the degradation activity of a wide variety of microorganisms involved in biodegradation.


Available from: Yuji Nagata, Jan 19, 2015
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