Biosynthesis of 3-Hydroxybutyrate-3-Hydroxyvalerate Copolymer by Methylobacteria with the Serine Metabolic Pathway

Melhylohacterium extorquens and Methylobrevibacter sp. 9 synthesized 3-hydroxybutyrate-3-hydroxyvalerate copolymer on a medium containing butanol in the presence of n-propanol, n-pentanol, propionate, and valerate. The addition of n-pentanol or valerate induced an increase in 3-hydroxyvalerate content in the 3-hydroxybutyrate-3-hydroxyvalerate copolymer in comparison to the contents of n-propanol and propionate. 2-¹⁴C-Valerate was incorporated in the copolymer. Carbon of 2-¹⁴C-propionate was used for the synthesis of cell components. Phenazine methosulfate-associated alcohol dehydrogenases and aldehyde dehydrogenases, as well as acyl coenzyme A (acyl CoA) synthetase are involved in the metabolism of n-propanol and n-pentanol in methylobacteria at initial stages of 3-hydroxybutyrate-3-hydroxyvalerate copolymer biosynthesis.