Desulfovibrio DA2_CueO is a novel multicopper oxidase with cuprous, ferrous and phenol oxidase activity

Microbiology (Reading). 2017 Aug;163(8):1229-1236. doi: 10.1099/mic.0.000509. Epub 2017 Jul 28.

Abstract

Desulfovibrio sp. A2 is a novel Gram-negative sulfate-reducing bacterium that was isolated from sediments of the Norilsk mining/smelting area in Russia. The organism possesses a monocistronic operon encoding a 71 kDa periplasmic multicopperoxidase, which we call DA2_CueO. Histidine-tagged DA2_CueO expressed from a plasmid in Escherichia coli and purified by Ni-NTA affinity chromatography oxidizes Cu+ and Fe2+, and exhibits phenol oxidase activity with 2,2-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid), 2,3-dihydroxybenzoic acid and 2,6-dimethoxyphenol as substrates, using O2 as the oxidant. When expressed in an E. coli cueO knock-out strain, DA2_CueO exhibits phenol oxidase activity in vivo and enhances the copper tolerance of the strain. These findings indicate that the DA2_CueO gene of Desulfovibrio sp. A2 encodes a multicopperoxidase with a role in metal ion resistance. The enzyme displays some novel structural features, which are discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / chemistry
  • Bacterial Proteins / genetics
  • Bacterial Proteins / isolation & purification
  • Bacterial Proteins / metabolism*
  • Copper / metabolism*
  • Desulfovibrio / chemistry
  • Desulfovibrio / enzymology*
  • Desulfovibrio / genetics
  • Desulfovibrio / isolation & purification
  • Ferrous Compounds / metabolism*
  • Geologic Sediments / microbiology
  • Oxidoreductases / chemistry
  • Oxidoreductases / genetics
  • Oxidoreductases / isolation & purification
  • Oxidoreductases / metabolism*
  • Phenol / metabolism*

Substances

  • Bacterial Proteins
  • Ferrous Compounds
  • Phenol
  • Copper
  • Oxidoreductases