Purification and characterization of a novel glycine oxidase from Bacillus subtilis

AbstractThe open reading frame yjbR which had been sequenced as a part of the Bacillus subtilis genome project encodes a putative 40.9-kDa protein. The yjbR-coding sequence was slightly similar to those of bacterial sarcosine oxidases and possibly compatible with the tertiary structure of the porcine kidney d-amino acid oxidase. The yjbR gene product was overproduced in Escherichia coli, purified to homogeneity from the recombinant strain, and characterized. This protein effectively catalyzed the oxidation of sarcosine (N-methylglycine), N-ethylglycine and glycine. Lower activities on d-alanine, d-valine, and d-proline were detected although no activities were shown on l-amino acids and other d-amino acids. Since glycine is a product and not a substrate for sarcosine oxidase, this protein is not a type of demethylating enzymes but a novel deaminating oxidase, named glycine oxidase as a common name. Several enzymatic properties of the B. subtilis glycine oxidase were also investigated