Cloning and sequencing of a novel meta-cleavage dioxygenase gene whose product is involved in degradation of γ-hexachlorocyclohexane in Sphingomonas paucimobilis

Keisuke Miyauchi, Yugo Adachi, Yuji Nagata, Masamichi Takagi

Research output: Contribution to journalArticle

89 Citations (Scopus)

Abstract

Sphingomonas (formerly Pseudomonas) paucimobilis UT26 utilizes γ- hexachlorocyclohexane (γ-HCH), a halogenated organic insecticide, as a sole source of carbon and energy. In a previous study, we showed that γ-HCH is degraded to chlorohydroquinone (CHQ) and then to hydroquinone (HQ), although the rate of reaction from CHQ to HQ was slow (K. Miyauchi, S. K. Suh, Y. Nagata, and M. Takagi, J. Bacteriol. 180: 1354-1359, 1998). In this study, we cloned and characterized a gene, designated linE, which is located upstream of linD and is directly involved in the degradation of CHQ. The Line protein consists of 321 amino acids, and all of the amino acids which are reported to be essential for the activity of meta-cleavage dioxygenases are conserved in LinE. Escherichia coli overproducing Line could convert both CHQ and HQ, producing γ-hydroxymuconic semialdehyde and maleylacetate, respectively, with consumption of O2 but could not convert catechol, which is one of the major substrates for meta-cleavage dioxygenases. Line seems to be resistant to the acylchloride, which is the ring cleavage product of CHQ and which seems to react with water to be converted to maleylacetate. These results indicated that Line is a novel type of meta-cleavage dioxygenase, designated (chloro)hydroquinone 1,2-dioxygenase, which cleaves aromatic rings with two hydroxyl groups at para positions preferably. This study represents a direct demonstration of a new type of ring cleavage pathway for aromatic compounds, the hydroquinone pathway.

Original languageEnglish
Pages (from-to)6712-6719
Number of pages8
JournalJournal of bacteriology
Volume181
Issue number21
DOIs
Publication statusPublished - 1999 Nov

ASJC Scopus subject areas

  • Microbiology
  • Molecular Biology

Fingerprint Dive into the research topics of 'Cloning and sequencing of a novel meta-cleavage dioxygenase gene whose product is involved in degradation of γ-hexachlorocyclohexane in Sphingomonas paucimobilis'. Together they form a unique fingerprint.

  • Cite this