title: Purification and amino acid composition of peptide antibiotic AS-48 produced by Streptococcus (Enterococcus) faecalis subsp. liquefaciens S-48.
abstract: Peptide antibiotic AS-48 was purified to homogeneity by ion-exchange chromatography, gel filtration chromatography, and reversed-phase liquid chromatography. The purified fraction was active against gram-positive and gram-negative bacteria. AS-48 is a basic protein with an isoelectric point of ca. 10.5 and a molecular mass of 7.4 kilodaltons. Its inhibitory activity was markedly affected by sodium dodecyl sulfate and cardiolipin but not by neuraminidase, pectinase, beta-glucosidase, or beta-glucuronidase. Differential scanning calorimetry data suggested that AS-48 molecules lack a compact structure.
authors.affiliation: Departamento de Microbiología, Facultad de Ciencias, Universidad de Granada, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Gálvez
authors.forename: G
authors.initials: G
authors.lastname: Giménez-Gallego
authors.forename: M
authors.initials: M
authors.lastname: Maqueda
authors.forename: E
authors.initials: E
authors.lastname: Valdivia
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000900:Anti-Bacterial Agents / Q000032:analysis / Q000096:biosynthesis / Q000302:isolation & purification*; D001426:Bacterial Proteins; D003470:Culture Media; D004355:Drug Stability; D004591:Electrophoresis, Polyacrylamide Gel; D013293:Enterococcus faecalis / Q000254:growth & development / Q000378:metabolism*; D007525:Isoelectric Focusing; D010452:Peptide Biosynthesis; D010455:Peptides / Q000032:analysis / Q000302:isolation & purification
chemical_list: D000596:Amino Acids; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D003470:Culture Media; D010455:Peptides; C051034:BacA protein, Enterococcus faecalis