title: Proteolytic fragments of ovalbumin display antimicrobial activity.
abstract: Ovalbumin, one of the major proteins present in avian egg white, was proteolytically digested by trypsin and chymotrypsin and the peptide fragments were investigated for their antimicrobial activity. The antimicrobial peptides were isolated and characterized. From the tryptic digestion, the following five antimicrobial peptide fragments were obtained: SALAM (residues 36-40), SALAMVY (residues 36-42) YPILPEYLQ (residues 111-119), ELINSW (residues 143-148) and NVLQPSS (residues 159-165). Digestion of ovalbumin by chymotrypsin yielded the antimicrobial peptides AEERYPILPEYL (residues 127-138), GIIRN (residues 155-159) and TSSNVMEER (residues 268-276). The peptides were synthesized and found to exert antimicrobial activity. They were strongly active against Bacillus subtilis and to a lesser extent against the other bacterial strains examined. A weak fungicidal activity against Candida albicans was also shown by some peptides. Ovalbumin itself was not bactericidal against all the bacteria strains examined. Our results suggest that the food protein ovalbumin may supply the organism with antimicrobial peptides, supporting the immunodefences of the organism.
authors.affiliation: Institute of Veterinary Physiology, University of Zürich Winterthurerstrasse 260, 8057 Zurich, Switzerland. pellegrinia@access.unizh.ch
authors.forename: Antonio
authors.initials: A
authors.lastname: Pellegrini
authors.forename: Andreas J
authors.initials: AJ
authors.lastname: Hülsmeier
authors.forename: Peter
authors.initials: P
authors.lastname: Hunziker
authors.forename: Ursula
authors.initials: U
authors.lastname: Thomas
mesh_terms: D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D000935:Antifungal Agents / Q000737:chemistry / Q000494:pharmacology*; D001419:Bacteria / Q000145:classification / Q000187:drug effects; D002176:Candida albicans / Q000187:drug effects; D002853:Chromatography, Liquid; D006868:Hydrolysis; D008826:Microbial Sensitivity Tests; D010047:Ovalbumin / Q000737:chemistry*; D010446:Peptide Fragments / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D010446:Peptide Fragments; D010047:Ovalbumin