title: A potent antibacterial protein in royal jelly. Purification and determination of the primary structure of royalisin.
abstract: A new potent antibacterial protein, for which we propose the name royalisin, was found in royal jelly of the honeybee Apis mellifera L. and purified to homogeneity for the first time by acid extraction, gel filtration, and reverse-phase high pressure liquid chromatography. The primary structure of royalisin was determined to consist of 51 residues, with three intramolecular disulfide linkages, having a calculated molecular mass of 5523 Da. Royalisin is an amphipathic protein, with the C-terminal half of the molecule being rich in charged amino acids; and it showed extensive sequence homology to two other antibacterial proteins, sapecin from embryonic Sarcophaga peregrina cells and phormicins from Phormia terranovae larvae. Royalisin was found to have potent antibacterial activity against Gram-positive bacteria at low concentrations, but not against Gram-negative bacteria. Royalisin may be involved in a defense system active against bacterial invasion of the honeybee.
authors.affiliation: Biochemical Research Laboratory, Morinaga Milk Industry Company Limited, Kanagawa, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Fujiwara
authors.forename: J
authors.initials: J
authors.lastname: Imai
authors.forename: M
authors.initials: M
authors.lastname: Fujiwara
authors.forename: T
authors.initials: T
authors.lastname: Yaeshima
authors.forename: T
authors.initials: T
authors.lastname: Kawashima
authors.forename: K
authors.initials: K
authors.lastname: Kobayashi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents; D001516:Bees / Q000378:metabolism*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D004220:Disulfides; D005227:Fatty Acids / Q000032:analysis*; D006094:Gram-Positive Bacteria / Q000187:drug effects; D007301:Insect Hormones; D019476:Insect Proteins; D036341:Intercellular Signaling Peptides and Proteins; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011506:Proteins / Q000302:isolation & purification* / Q000494:pharmacology; D012689:Sequence Homology, Nucleic Acid; D000099219:Royal Jelly
chemical_list: D000900:Anti-Bacterial Agents; D004220:Disulfides; D005227:Fatty Acids; D007301:Insect Hormones; D019476:Insect Proteins; D036341:Intercellular Signaling Peptides and Proteins; D011506:Proteins; D000099219:Royal Jelly; C064723:phormicin A; C057638:sapecin protein, Sarcophaga; C064722:royalisin