Biosynthesis of novel copolyesters containing 3-hydroxypivalic acid by Rhodococcus ruber NCIMB 40126 and related bacteria

• Published in: FEMS microbiology letters 1998-02, Vol.159 (1), p.85-92
• Main Authors: Füchtenbusch, Bernd, Fabritius, Dirk, Wältermann, Marc, Steinbüchel, Alexander
• Format: Article
• Language: English
• Subjects: 2,2‐Dimethyl‐3‐hydroxypropionic acid; 3‐Hydroxybutyric acid; 3‐Hydroxypivalic acid; Acids; Bacteria; Biosynthesis; Carbon; Carbon sources; Coenzyme A; Gas chromatography; Gram-positive bacteria; Hydroxyvaleric acid; Mass spectrometry; Mass spectroscopy; Microbiology; NMR; Nuclear magnetic resonance; Polyhydroxyalkanoates; Polyhydroxyalkanoic acid; Rhodococcus; Rhodococcus ruber; Salts; Scientific imaging; Spectroscopy; Substrates
• ISSN: 0378-1097; 1574-6968
• DOI: 10.1111/j.1574-6968.1998.tb12845.x

Abstract Rhodococcus ruber and related Gram-positive bacteria synthesized and accumulated novel copolyesters containing 3-hydroxypivalic acid as constituent if the cells were cultivated in a mineral salts medium containing 3-hydroxypivalic acid and glucose as carbon sources. The copolyesters contributed 0.4–10% of the cellular dry mass, and they contained up to 78 mol% of 3-hydroxypivalic acid in addition to 3-hydroxybutyric acid and 3-hydroxyvaleric acid; a homopolyester of 3-hydroxypivalic acid was also synthesized under certain conditions. The presence of 3-hydroxypivalic acid in the accumulated copolyesters was confirmed by nuclear magnetic resonance spectrometry as well by coupled gas chromatography/mass spectrometry. This is the first time that the incorporation of 3-hydroxypivalic acid and therefore of a hydroxyalkanoic acid with two methyl group substituents at the α-carbon atom in a naturally occurring copolyester is reported. It indicates that 3-hydroxypivalic acid-coenzyme A is accepted by polyhydroxyalkanoic acid synthase as a substrate.