Pyruvic oxime dioxygenase from heterotrophic nitrifier Alcaligenes faecalis is a nonheme Fe^(II)-dependent enzyme homologous to class II aldolase.

ABSTRACT: Pyruvic oxime dioxygenase (POD), a key enzyme in heterotrophic nitrification, was purified from Alcaligenes faecalis, and the molecular and catalytic characteristics were reexamined. POD was purified as the homotetramer of the subunit whose molecular weight was 30,000. The deduced amino acid sequence of POD was homologous with a class II aldolase that has been regarded as the Zn^(II)-dependent enzyme catalyzing aldol reactions. The recombinant protein showed weak POD activity, and was activated by reconstitution with Fe^(II). Affinity and catalytic constants were estimated at 470 μM and 4.69 sec^-1, respectively. The POD was inactivated by EDTA to remove bound divalent metal cations. A reconstitution experiment demonstrated that Fe^(II), not Zn⁽

SUBMITTER: Tsujino S 

PROVIDER: S-EPMC5216522 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature