title: Relationship between valine, fatty acids, and spiramycin biosynthesis in Streptomyces ambofaciens.
abstract: Spiramycin biosynthesis in Streptomyces ambofaciens was stimulated in the presence of valine or by sequential addition of some short-chain fatty acids to a culture medium containing an ammonium salt as source of nitrogen. Acetate kinase and acetyl-CoA carboxylase, enzymes that catalysed the formation of precursors of spiramycin biosynthesis (acetyl-CoA and malonyl-CoA), were detected during the active growth and antibiotic production phases. In this latter phase a higher level of acetyl-CoA carboxylase activity was observed with valine (1.02 mumol.min-1.mg protein-1) than with ammonium (0.05 mumol.min-1.mg protein-1) as nitrogen source, while the evolution and the level of acetate kinase activity were the same in both media. Successive addition of acetate and isobutyrate stimulated highly and weakly the acetyl-CoA carboxylase and acetate kinase activity, respectively.
authors.affiliation: Laboratoire de microbiologie industrielle, ENSAIA, Institut national polytechnique de Lorraine, Vandoeuvre, France.
authors.forename: M
authors.initials: M
authors.lastname: Laakel
authors.forename: A
authors.initials: A
authors.lastname: Lebrihi
authors.forename: S
authors.initials: S
authors.lastname: Khaoua
authors.forename: F
authors.initials: F
authors.lastname: Schneider
authors.forename: G
authors.initials: G
authors.lastname: Lefebvre
authors.forename: P
authors.initials: P
authors.lastname: Germain
mesh_terms: D000084:Acetate Kinase / Q000032:analysis; D000085:Acetates / Q000378:metabolism; D000103:Acetyl-CoA Carboxylase / Q000032:analysis; D000643:Ammonium Chloride / Q000378:metabolism; D002087:Butyrates / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism*; D058610:Isobutyrates; D015572:Spiramycin / Q000096:biosynthesis*; D013302:Streptomyces / Q000187:drug effects / Q000378:metabolism*; D014633:Valine / Q000378:metabolism*
chemical_list: D000085:Acetates; D002087:Butyrates; D005227:Fatty Acids; D058610:Isobutyrates; D000643:Ammonium Chloride; D015572:Spiramycin; C020380:isobutyric acid; D000084:Acetate Kinase; D000103:Acetyl-CoA Carboxylase; D014633:Valine