A Particulate Pyridine Nucleotide Oxidase System of the Wheat Embryo.

Abstract

In homo-genates of viable wheat embryos 80% of the capacity to oxidize DPNH and TPNH independently of the cytochrome system is localized in particulate structures. These particles are readily separated from the mitochondria by differential centrifugation. The oxidase system has properties in common with those previously described for soluble oxidase preparations. It has a specific requirement for Mn++, and is inhibited by catalase and a variety of reducing agents, most effectively by ascorbic acid. H2O2 is a reaction product, which in the presence of an appropriate acceptor (p-aminobenzoic and anthranilic acids) is reduced by the peroxidase component of the system.