Identification and characterization of the chromium (VI) responding protein from a newly isolated Ochrobactrum anthropi CTS-325

J Environ Sci (China). 2009;21(12):1673-8. doi: 10.1016/s1001-0742(08)62472-9.

Abstract

A Gram-negative, chromium(VI) tolerant and reductive strain CTS-325, isolated from a Chinese chromate plant, was identified as Ochrobactrum anthropi based on its biochemical properties and 16S rDNA sequence analysis. It was able to tolerate up to 10 mmol/L Cr(VI) and completely reduce 1 mmol/L Cr(VI) to Cr(III) within 48 h. When the strain CTS-325 was induced with Cr(VI), a protein increased significantly in the whole cell proteins. Liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis revealed that this protein was a superoxide dismutase (SOD) homology. The measured superoxide dismutase activity was 2694 U/mg after three steps of purification. The SOD catalyzes the dismutation of the superoxide anion (O2*-) into hydrogen peroxide and molecular oxygen. This protein is considered to be one of the most important anti-oxidative enzymes for O. anthropi as it allows the bacterium to survive high oxygen stress environments, such as the environment produced during the reduction process of Cr(VI).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Chromatography, Liquid
  • Chromium / metabolism*
  • Electrophoresis, Polyacrylamide Gel
  • Mass Spectrometry
  • Molecular Sequence Data
  • Ochrobactrum anthropi / enzymology*
  • Ochrobactrum anthropi / genetics
  • Ochrobactrum anthropi / isolation & purification
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Superoxide Dismutase / genetics
  • Superoxide Dismutase / isolation & purification
  • Superoxide Dismutase / metabolism*

Substances

  • Bacterial Proteins
  • Chromium
  • Superoxide Dismutase