Purification and properties of peptides which induce germination of blastospores of Candida albicans.

A glycopeptide and a peptide have been isolated from bovine seminal plasma which together will induce germination of Candida albicans blastospores at 37 degrees C and in the presence of glucose and Mn2+. ¿They have molecular weights of 2000 to 3000. Both peptides contain appreciable amounts of aspartic and glutamic acids, only the glycopeptide contains threonine, lysine, histidine and arginine, while only the peptide contains proline. Acid hydrolysates are fully active in inducing germination and a mixture of aspartic acid, lysine, histidine, threonine, proline and beta-alanine can replace them. Mn2+ is not then required. Amino acid mixtures are required to be present throughout the whole period in the incubation medium for full germination to take place, but the peptides can be removed after 1 h incubation and if the cells are resuspended in a buffered glucose medium full germination occurs after a further 3 h incubation.