title: Effects of rapessed oil on activity of methylmalonyl-CoA carboxyltransferase in culture of Streptomyces fradiae.
abstract: To investigate why more tylosin was produced when Streptomyces fradiae T1558 was cultured in a rapeseed oil medium than in a glucose or starch medium, we measured the activity of methylmalonyl-CoA carboxyltransferase (EC 2.1.3.1) and intracellular propionic acid. The activity of the enzyme, which catalyzes the formation of the precursor of tylosin, protylonolide, was 0.19 U/mg protein in 5 days of culture in rapeseed oil medium, which was 2.5- and 1.3-fold that with the glucose or starch medium, respectively. The intracellular propionic acid concentration was 1.2 g/g of dry weight, which was 4.3- and 2.1-fold that with the glucose or starch medium, respectively. The addition of propionic acid increased tylosin production in batch culture: when 0.2 g/l (final concentration) propionic acid was added to the glucose medium, 3.8 g/l tylosin was produced in 10 days of culture, 4.7-fold the amount without propionic acid. These findings suggest that in glucose medium, intracellular propionic acid is a limiting factor because of the low activity of methylmalonyl-CoA carboxyltransferase of the tylosin biosynthesis pathway.
authors.affiliation: United Graduate School of Agricultural Science, Gifu University, Japan.
authors.forename: D B
authors.initials: DB
authors.lastname: Choi
authors.forename: Y
authors.initials: Y
authors.lastname: Park
authors.forename: M
authors.initials: M
authors.lastname: Okabe
mesh_terms: D019880:Aldehyde-Ketone Transferases / Q000378:metabolism*; D019878:Carboxyl and Carbamoyl Transferases / Q000187:drug effects* / Q000378:metabolism*; D005229:Fatty Acids, Monounsaturated; D010938:Plant Oils / Q000494:pharmacology*; D011422:Propionates / Q000494:pharmacology; D000074262:Rapeseed Oil; D013302:Streptomyces / Q000201:enzymology*; D015645:Tylosin / Q000031:analogs & derivatives* / Q000096:biosynthesis
chemical_list: D005229:Fatty Acids, Monounsaturated; D010938:Plant Oils; D011422:Propionates; D000074262:Rapeseed Oil; C027411:protylonolide; D019878:Carboxyl and Carbamoyl Transferases; C021580:Methylmalonyl-CoA carboxytransferase; D019880:Aldehyde-Ketone Transferases; C029658:propionic acid; D015645:Tylosin