RESEARCH HIGHLIGHTS - Enhanced production of polyhydroxyalkanoate with manipulable and reproducible 3-hydroxyvalerate fraction by high alcohol tolerant Cupriavidus malaysiensis USMAA2-4 transformant

by H.S.J. Wong · N.A. Azami · A.A.A. Amirul

The domination of high-cost organic acids over other 3-hydroxyvalerate (3HV) precursors due to the wide preference among polyhydroxyalkanoates (PHA)-producing bacteria has limited the development of diverse poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] production processes. 1-pentanol is a low-cost 3HV precursor but is rarely employed due to the relatively low tolerance among PHA-producing bacteria. It can be oxidized to pentanal and further oxidized to valeric acid, thus can be employed as a substitute for high-cost valeric acid preferred by most PHA-producing bacteria in P(3HB-co-3HV) production. This study demonstrated P(3HB-co-3HV) production by Cupriavidus malaysiensis USMAA2-4_ABh16 which is the transformant strain with acquired lipase genes that retains the tolerance towards 1-pentanol of its wild-type with manipulable 3HV composition between 6−15 mol% and reproducible selected 3HV composition and the respective 3HV yield from palm olein and 1-pentanol at a 120-fold larger scale. The P(3HB-co-3HV) produced displayed higher flexibility than polypropylene and P(3HB-co-3HV) produced from different carbon sources. C. malaysiensis USMAA2-4_ABh16 could be practically applicable for sustainable and economically feasible P(3HB-co-3HV) production on an industrial scale from used palm olein with relatively similar oleic acid content with palm olein and 1-pentanol, with higher 3HV compositions achievable through fed-batch strategies owing to its high 1-pentanol tolerance.


Link:  https://link.springer.com/article/10.1007/s00449-022-02748-2

CCB Ref.:  2022_RH_naa_01
Date :  28/09/2022