title: VisG is essential for biosynthesis of virginiamycin S, a streptogramin type B antibiotic, as a provider of the nonproteinogenic amino acid phenylglycine.
abstract: A streptogramin type B antibiotic, virginiamycin S (VS), is produced by Streptomyces virginiae, together with a streptogramin type A antibiotic, virginiamycin M1 (VM), as its synergistic counterpart. VS is a cyclic hexadepsipeptide containing a nonproteinogenic amino acid, Lphenylglycine (L-pheGly), in its core structure. We have identified, in the left-hand extremity of the virginiamycin supercluster, two genes that direct VS biosynthesis with L-pheGly incorporation. Transcriptional analysis revealed that visF, encoding a nonribosomal peptide synthetase, and visG, encoding a protein with homology to a hydroxyphenylacetyl-CoA dioxygenase, are under the transcriptional regulation of virginiae butanolide (VB), a small diffusing signalling molecule that governs virginiamycin production. Gene deletion of visG resulted in complete loss of VS production without any changes in VM production, suggesting that visG is required for VS biosynthesis. The abolished VS production in the visG disruptant was fully recovered either by the external addition of pheGly or by gene complementation, which indicates that VisG is involved in VS biosynthesis as the provider of an L-pheGly molecule. A feeding experiment with L-pheGly analogues suggested that VisF, which is responsible for the last condensation step, has high substrate specificity toward L-pheGly.
authors.affiliation: International Center for Biotechnology, Osaka University, 2-1, Yamadaoka, Suita, Osaka 565-0871, Japan.
authors.forename: Fitria
authors.initials: F
authors.lastname: Ningsih
authors.affiliation: International Center for Biotechnology, Osaka University, 2-1, Yamadaoka, Suita, Osaka 565-0871, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kitani
authors.affiliation: International Center for Biotechnology, Osaka University, 2-1, Yamadaoka, Suita, Osaka 565-0871, Japan.
authors.forename: Eriko
authors.initials: E
authors.lastname: Fukushima
authors.affiliation: MU-OU Collaborative Research Center for Bioscience and Biotechnology, Faculty of Science, Mahidol University, Rama VI Rd, Bangkok 10400, Thailand.|International Center for Biotechnology, Osaka University, 2-1, Yamadaoka, Suita, Osaka 565-0871, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Nihira
mesh_terms: D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000096:biosynthesis*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D017353:Gene Deletion; D015964:Gene Expression Regulation, Bacterial; D005816:Genetic Complementation Test; D005998:Glycine / Q000031:analogs & derivatives*; D008969:Molecular Sequence Data; D005810:Multigene Family; D012329:RNA, Bacterial / Q000235:genetics; D025382:Streptogramin Group B / Q000096:biosynthesis*; D013302:Streptomyces / Q000235:genetics / Q000378:metabolism*; D013379:Substrate Specificity; D014769:Virginiamycin / Q000096:biosynthesis*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D012329:RNA, Bacterial; D025382:Streptogramin Group B; D014769:Virginiamycin; C418083:virginiamycin factor S1; D005998:Glycine