PEPTIDES REQUIRED FOR THE GROWTH OF LACTOBACILLUS BULGARICUS

Abstract
Jones , K. M. (The Rockefeller Institute, New York, N. Y.) and D. W. Woolley . Peptides required for the growth of Lactobacillus bulgaricus . J. Bacteriol. 83: 797–801. 1962.— Lactobacillus bulgaricus 09 had an absolute requirement for growth for a suitable peptide, which was satisfied by trypsinized casein or hemoglobin. Digests of globin and the α and β chains derived from it showed similar activity to hemoglobin digests. Each of four highly purified peptides of different amino acid composition isolated from the α chain of globin had activity. Each active peptide had seven or more residues; smaller peptides were inactive. The requirement for L. bulgaricus was not one for strepogenin because some substances with strepogenin activity for L. casei were not active for L. bulgaricus .