Dehalobacter restrictus gen. nov. and sp. nov., a strictly anaerobic bacterium that reductively dechlorinates tetra- and trichloroethene in an anaerobic respiration

Arch Microbiol. 1998 Apr;169(4):313-21. doi: 10.1007/s002030050577.

Abstract

The highly enriched anaerobic bacterium that couples the reductive dechlorination of tetrachloroethene to growth, previously referred to as PER-K23, was obtained in pure culture and characterized. The bacterium, which does not form spores, is a small, gram-negative rod with one lateral flagellum. It utilized only H2 as an electron donor and tetrachloroethene and trichloroethene as electron acceptors in an anaerobic respiration process; it could not grow fermentatively. Acetate served as a carbon source in a defined medium containing iron as the sole trace element, the two vitamins thiamine and cyanocobalamin, and the three amino acids arginine, histidine, and threonine. The cells contained menaquinones and b-type cytochromes. The G+C content of the DNA was 45.3 +/- 0.3 mol%. The cell wall consisted of type-A3gamma peptidoglycan with ll-diaminopimelic acid and one glycine as an interpeptide bridge. The cells are surrounded by an S-layer; an outer membrane was absent. Comparative sequence analysis of the 16S rRNA sequence showed that PER-K23 is related to gram-positive bacteria with a low G+C content of the DNA. Based on the cytological, physiological, and phylogenetic characterization, it is proposed to affiliate the isolate to a new genus, Dehalobacter, with PER-K23 as the type strain of the new species Dehalobacter restrictus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anaerobiosis
  • Bacteria, Anaerobic / genetics
  • Bacteria, Anaerobic / metabolism*
  • Bacteria, Anaerobic / ultrastructure
  • Cell Division / physiology
  • Oxidation-Reduction
  • Phylogeny
  • RNA, Ribosomal, 16S / analysis
  • RNA, Ribosomal, 16S / genetics
  • Tetrachloroethylene / metabolism*
  • Trichloroethylene / metabolism*

Substances

  • RNA, Ribosomal, 16S
  • Trichloroethylene
  • Tetrachloroethylene