Mn(II) oxidation is catalyzed by heme peroxidases in "Aurantimonas manganoxydans" strain SI85-9A1 and Erythrobacter sp. strain SD-21.

ABSTRACT: A new type of manganese-oxidizing enzyme has been identified in two alphaproteobacteria, "Aurantimonas manganoxydans" strain SI85-9A1 and Erythrobacter sp. strain SD-21. These proteins were identified by tandem mass spectrometry of manganese-oxidizing bands visualized by native polyacrylamide gel electrophoresis in-gel activity assays and fast protein liquid chromatography-purified proteins. Proteins of both alphaproteobacteria contain animal heme peroxidase and hemolysin-type calcium binding domains, with the 350-kDa active Mn-oxidizing protein of A. manganoxydans containing stainable heme. The addition of both Ca(2+) ions and H(2)O(2) to the enriched protein from Aurantimonas increased manganese oxidation activity 5.9-fold, and the highest activity recorded was 700 microM min(-1) mg(-1).

SUBMITTER: Anderson CR 

PROVIDER: S-EPMC2698374 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature