title: Purification of three antibacterial proteins from the culture medium of NIH-Sape-4, an embryonic cell line of Sarcophaga peregrina.
abstract: Three antibacterial proteins were purified from the culture medium of NIH-Sape-4, an embryonic cell line of Sarcophaga peregrina (flesh fly). Sequencing studies showed that two of these proteins belong to the sarcotoxin I family, potent antibacterial proteins purified from the hemolymph of Sarcophaga larvae, whereas the other protein, named sapecin, is a new protein consisting of 40 amino acid residues including 6 cysteine residues. Unlike sarcotoxin I, sapecin preferentially represses the growth of various Gram-positive bacteria. The proteins of the sarcotoxin I family produced by this cell line were found to have carboxyl-terminal glycine, whereas sarcotoxin I in the hemolymph has amidated amino acids. This suggests that the embryonic cells lack an enzyme that cleaves off carboxyl-terminal glycine to form a new amidated carboxyl terminus.
authors.affiliation: Faculty of Pharmaceutical Sciences, University of Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Matsuyama
authors.forename: S
authors.initials: S
authors.lastname: Natori
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000302:isolation & purification*; D002460:Cell Line; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D003470:Culture Media; D004175:Diptera / Q000032:analysis*; D006458:Hemolymph / Q000032:analysis; D007301:Insect Hormones / Q000032:analysis / Q000302:isolation & purification*; D019476:Insect Proteins; D008969:Molecular Sequence Data
chemical_list: D000900:Anti-Bacterial Agents; D003470:Culture Media; D007301:Insect Hormones; D019476:Insect Proteins; C057638:sapecin protein, Sarcophaga; C042572:sarcotoxin I protein, Sarcophaga peregrina