Biosynthesis of 5-hydroxy-4-oxo-L-norvaline in Streptomyces akiyoshiensis

White, RL; Smith, KC; Demarco, AC

HERO ID

4932902

Reference Type

Journal Article

Year

1994

HERO ID 4932902
In Press No
Year 1994
Title Biosynthesis of 5-hydroxy-4-oxo-L-norvaline in Streptomyces akiyoshiensis
Authors White, RL; Smith, KC; Demarco, AC
Journal Canadian Journal of Chemistry
Volume 72
Issue 7 (1994)
Page Numbers 1645-1655
Abstract The biosynthesis of 5-hydroxy-4-oxo-L-norvaline (HON) in Streptomyces akiyoshiensis has been investigated using super(13)C-labelled substrates. Incorporations of super(13)C label from sodium [1- super(13)C]-, [2- super(13)C]-, and [1,2- super(13)C sub(2)]acetate indicated that HON was formed from a four-carbon compound derived from the citric acid cycle and the methyl carbon of acetate. Feeding experiments using DL-[4- super(13)C]- and DL-[2- super(13)C, super(15)N]aspartate demonstrated that aspartate served as the four-carbon precursor to HON. Both enantiomers of aspartate were metabolized by S. akiyoshiensis, but the D isomer was consumed at a slower rate. The distribution of super(13)C label in the intracellular L-glutamic acid isolated in these feeding experiments is consistent with the operation of the citric acid cycle in S. akiyoshiensis. A biosynthetic hypothesis that involves a condensation reaction between acetyl or malonyl CoA and the beta -carboxyl group of aspartate, and subsequent oxidative decarboxylation, is proposed to account for the incorporation results. An analogous condensation step has been proposed for the biosynthesis of other natural products, including the carbapenem antibiotics. DL-[2- super(13)C, super(15)N]Aspartate was synthesized from [2- super(13)C]diethylmalonate and potassium [ super(15)N]phthalimide via diethyl [2- super(13)C, super(15)N]phthalimidomalonate.
Doi 10.1139/v94-207
Wosid WOS:A1994NY88400008
Is Certified Translation No
Dupe Override No
Is Public Yes
Keyword anabolism; amino acids