Characterization of a Multi-Copper Enzyme, Nitrous Oxide Reductase, from Rhodobacter sphaeroides f. sp. denitrificans

Abstract

The nitrous oxide reductase from the photodenitrifier, Rhodobacter sphaeroides f. sp. denitrificans, has been purified. The enzyme is composed of two identical subunits of 66 kDa, and contains four copper atoms per subunit. Copper supplementation of the medium resulted in a 3.5-fold increase in the enzyme yield with doubly enhanced specific activity. The activity of the purified nitrous oxide reductase was completely inhibited by 100 μM zinc ions.