Amino Acids in the Biosynthesis of Penicillin

SUMMARY

When grown on a basal medium with the addition of single amino acids as sole sources of nitrogen in quantities equivalent to 50 mg. per cent of nitrogen, Penicillium chrysogenum Q-176 is able to produce small amounts of penicillin from glycine, alanine, beta-alanine, serine, threonine, arginine, aspartic acid, asparagine, glutamic acid, proline, and hydroxyproline. No penicillin is produced from leucine, isoleucine, norleucine, valine, histidine, lysine, cystine, methionine, cysteine, tryptophane, tyrosine, or phenylalanine under identical conditions. None of the amino acids tested is superior to nitrate as a source of nitrogen for penicillin biosynthesis.