IDENTIFICATION OF BARLEY OXALATE OXIDASE AS A GERMIN-LIKE PROTEIN

A barley oxalate oxidase was purified to homogeneity and the N-termina l sequences of the protein and of two peptides generated by CNBr cleav age of this protein were determined. Searches for similarities in data bank revealed that the sequences are highly homologous to the amino-a cid sequence of a wheat protein, germin, which is synthesized de novo during germination. The similarity of the two proteins was confirmed b y showing that anti-oxalate oxidase antibodies strongly recognize germ in produced in Escherichia coli. We show that like germin, oxalate oxi dase is glycosylated, resistant to SDS denaturation, heat stable, and protease resistant Moreover, oxalate oxidase activity is strongly indu ced during germination of barley embryos resulting from an accumulatio n of the protein. Thus, we conclude that barley oxalate oxidase is a g ermin-like protein.