Abstract
Canavanine was detected in the protein + cell wall fraction of S. aureus 524 grown in its presence. No canavanine could be detected in cell-wall preparations from cells grown in the presence of arginine under similar conditions. The canavanine was incorporated in the protein + cell wall fraction in such a way that the amino group of the amino acid was not free to react with l-fluoro"-2:4-dinitrobenzene.