• Korean Journal of Microbiology
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• v.40 no.2
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• pp.121-126
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• 2004

Comamonas sp. strain DJ-12 is a 4-chlobiphenyl(4CB)-degrading bacterium that was reidentified from Pseudomonas sp. DJ-12. The genomic DNA was isolated from the strain DJ-12 and amplified by PCR with primers for cloning pcbABCD genes responsible for degradation of 4CB. The amino acid sequences deduced from the nucleotide sequences of pcbA1, pcbA2, pcbA3, pcbA4, pcbB, pcbC2, and pcbD2 genes showed 91, 87, 99, 87, 97, 90 and 87％ homologies with those of Pseudomonas sp. KKS102, respectively. The pcbC1D1 genes that are involved in the degradation of (4-chloro)1,2-dihydroxybiphenyl produced from 4CB by pcbAB gene products were previously reported in the recombinant plasmid pCU1 from Pseudomonas sp. DJ-12. However, the pcbC2D2 genes in the plasmid pCT4 and pCT5 cloned from Comamonas sp. DJ-12 in this study showed 51 and 62％ homologies with those of pcbC1D1 in their nucleotide sequences. The pcbC1D1 and pcbC2D2 genes were found by Southern hybridization to be located at different loci on the chromosome of DJ-12 strain. These results indicate that Comamonas sp. strain DJ-12 has two different sets of pcbCD genes responsible for deg-radation of (4-chloro)1,2-dihydroxybiphenyl.

• Korean Journal of Microbiology
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• v.41 no.3
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• pp.195-200
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• 2005

Comamonas sp. strain DJ-12 is a bacterial isolate capable of degrading of 4-chlorobiphenyl (4CB) as a carbon and energy source. The degradation pathway was characterized as being conducted by consecutive reactions of the meta-degradation of 4CB, hydrolytic dechlorination of 4-chlorobenzoate (4CBA), hydroxylation of 4-hydroxybenzoate, and meta-degradation of protocatechuate to product TCA metabolites. The 6.8 kb fragment from the chromosomal DNA of Comamonas sp. strain DJ-12 included the genes encoding for the meta-degradation of PCA; the genes of protocatechuate 4,5-dioxygenase alpha and beta subunits (pmcA and pmcB), 4-carboxy-2-hydroxymuconate-6-semialdehyde dehydrogenase (pmcC), 2-pyrone-4,6-dicarboxylate hydrolase (pmcD), 4-oxalomesaconate (OMA) hydratase(pmcE), 4-oxalocitramalate (OCM) aldolase (pmcF), and transporter gene (pmcT). They were organized in the order of pmcT-pmcE-pmcF-pmcD-pmcA-pmcB-pmcC. The amino acid sequences deduced from the nucleotide sequences of pmcABCDEFT genes from Comamonas sp. strain DJ-12 exhibited 94 to $98\%$ homologies with those of Comamonas testosteroni BR6020 and Pseudomonas ochraceae NGJ1, but only 52 to $74\%$ with homologies Sphingomonas paucimobilis SYK-6, Sphingomonas sp. LB126, and Arthrobacter keyseri 12B.

• Journal of Microbiology
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• v.41 no.2
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• pp.89-94
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• 2003

Bacterial strain No. P08 isolated from wastewater at the Cheongju industrial complex was found to be capable of degrading 4-chlorobenzoate under aerobic condition. P08 was identified as Comamonas sp. from its cellular fatty acid composition and 16S rDNA sequence. The fcb genes, responsible for the hydrolytic dechlorination of 4-chlorobenzoate, were cloned from the plasmid pJJl of Comamonas sp. P08. The fcb gene cluster of comamonas sp. PO8 was organized in the order fcbB-fcbA-fcbTl-fcbT2-fcbT3-fcbC. This organization of the fcb genes was very similar to that of the fcb genes carried on the chromosomal DNA of pseudomonas sp. DJ-12. However, it differed from the fcbA-fcbB -fcbC ordering of Arthrobacter sp. SU. The nucleotide sequences of the fcbABC genes of strain P08 showed 98% and 53% identities to those of Pseudomonas sp. DJ-12 and Arthrobacter sp. SU, respectively. This suggests that the fcb genes might have been derived from Pseudomonas sp. DJ-12 to form plasmid pJSl in Comamonas sp. P08, or that the fcb genes in strain DJ-12 were transposed from Comamonas sp. P08 plasmid.