• Korean Journal of Microbiology
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• v.31 no.2
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• pp.129-134
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• 1993

The pchAB genes of Pseudomonas sp. DJ-12 produce the enzymes of 4-chlorobipheny] (4CB) dioxygenase and dihydrodiol dehydrogenase which act on the first and second steps in degradation of 4CB and biphenyl. The genes were cloned in E coli XLI-Blue. The pcbAB genes of about 2.2 kb in size were contained in the pCUlO1 hybrid plasmid in the cloned cell of CUIOI. The genes were found to have their own promoter and three restriction sites for HindlII. 2,3-dihydroxybiphenyl was detected by the resting cell assay, as the metabolite transformed from biphenyl by the cloned cell of CUIOI. This means that the pcbAB genes are well expressed in E. coli. But dechlorination was unlikely involved in the pchAB gene expression but was believed to occur by functioning on 4CBA produced after ring-cleavage of 4CB.

• Microbiology and Biotechnology Letters
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• v.22 no.1
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• pp.37-44
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• 1994

The homology among the genes coding for degradation of bipheny(BP) and 4-chlorobiphenyl(4CB) was comparatively analyzed by Southern hybridization in several BP/4CB degrading bacterial strains. As the hybridization results of their genomic DNAs with pcbABCD as the DNA probe, the group of Pseudomonas sp. DJ-12. P08 and P27 strain was separated by the group of P20 and P1242 strains. The P. pseudoalcaligenes KF707 showed the hybidization signal which was homologous to the group of DJ-12, but they had different restriction endonuclease sites. The pcbAB genes in pCUl recombinant plasmid from Pseudomonas sp. DJ-12 appeared to be homologous to pchAB genes in pKTF20 cloned from P. pseudoalcaligenes KF707, but the C genes in both strains were not homologous. The bphABC in pKTF20 showed the signals homologous to the cbp ACB in pAW6194 cloned from P. putida OU83, but homologous signal was not found botween the pcbABCD genes in pCUl and the cbpADCB genes in pAW6194 recombbinant plasmid.

• Korean Journal of Microbiology
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• v.32 no.2
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• pp.126-131
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• 1994

The pchABCD genes in Pseudomonas sp. DJ-12 speciyin degradation o 4-chlorobiphenyl(4CB) were cloned in Eschericia coli. The cloned cells of E. coli CU1 and CU101 showed to produce 2,3-dihydroxybiphenyl (2,3-DHBP) from 4-chlorobiphenyl by dechlorination, as Pseudomonas so. DJ-12 produced 2,3-DHBP from both biphenyl and 4CB. In particular, E. coli CU101 transformed with the recombinant plasmid of pCU101 revealed dechlorination activity to produce 2,3-DHBP from 4CB without production of 4-chlorobenzoic acid. Therefore, the pcbAB genes (2.2 kb in size) cloned from the chromosome of Pseudomonas sp. DJ-12 were found to have dechlorination activity on 4CB to produce 2,3-DHNP.