Molecular cloning of a Pseudomonas paucimobilis gene encoding a 17-kilodalton polypeptide that eliminates HCl molecules from gamma-hexachlorocyclohexane

Abstract

Pseudomonas paucimobilis UT26 is capable of growing on 'y-hexachlorocyclohexane (,y-HCH). A genomic library of P. paucimobilis UT26 was constructed in Pseudomonas putida by using the broad-host-range cosmid vector pKS13. After 2,300 clones were screened by gas chromatography, 3 clones showing y-HCH degradation were detected. A 5-kb fragment from one of the cosmid clones was subcloned into pUC118, and subsequent deletion and gas chromatography-mass spectrometry analyses revealed that a fragment of ca. 500 bp was responsible for the conversion of y-HCH to 1,2,4-trichlorobenzene via -y-pentachlorocyclohexene. Nucleotide sequence analysis revealed an open reading frame (linA) of 465 bp within the fragment. The nucleotide sequence of the linA gene and the deduced amino acid sequence showed no similarity to any known sequences.

Localization of HCH catabolic genes (lin genes) in Sphingobium indicum B90A

“…All the HCH catabolic genes (called lin genes) involved in the degradation of γ-HCH isomer have been identifi ed in S. japonicum UT26 3,4 . The primary enzyme in γ-HCH degradation is HCH dehydrochlorinase encoded by linA 5 . The remaining genes of the γ-HCH degradative pathway are linB 6 , linC 7 , linD 8 , linE/linEb 9,10 , linF 10 , linGH 4 and linJ 4 encoding haloalkane dehalogenase, dehydrogenase, reductive dechlorinase, ring-cleavage oxygenase, maleylacetate reductase, acyl-CoA transferase and thiolase, respectively.…”

Purification and Characterization ofγ-Hexachlorocyclohexane (γ-HCH) Dehydrochlorinase (LinA) fromPseudomonas paucimobilis

“…2), as expected. 3) The substrate specificity of LinA was examined. It was suggested that the activity of LinA would be very specific to y-HCH and its metabolic intermediate y-PCCH.…”

Proceedings of the 2001 ECBC Scientific Conference on Chemical and Biological Defense Research, 6-8 March 2001, Marriott's Hunt Valley Inn, Hunt Valley, MD

“…A bacterial strain, Sphingomonas paucimobilis UT26 (formerly known as Pseudomonas paucimobilis UT26), was found to grow on hexachlorocyclohexane (HCH, or lindane) as a sole source of carbon Imai, 1989). Subsequently, the enzymes involved in HCH degradation had been purified (Nagata, 1993a) and the relevant genes in the metabolic pathway were cloned and sequenced (Imai, 1991;Nagata, 1993bNagata, , 1994Miyauchi, 1998).…”