Investigation the effect of acetoacetanilide inhibitor on growth and Beta Carotene production in Blakeslea trispora

BACKGROUND AND OBJECTIVESBlakeslea trispora, accumulates high amount of β-carotene from the biological sources under sexual interaction conditions. B. trispora possesses conserved carotenoid biosynthetic pathway (CBP) and Carotenoids are derived from the five-carbon isoprene units, isopentenyl diphosphate (IPP) via the mevalonate pathway (MVA). In the present work, one of the metabolic inhibitors like acetoacetanilide was used in a defined medium, as repeated batch cultures, to understand their influence on carotenoid biosynthesis. Acetoacetanilide is a preferred acetate analog that inhibits acetoacetyl-CoA synthetase (AACS) in the first step of the carotenoid biosynthesis pathway.MATERIALS AND METHODSB. trispora PTCC۵۲۷۸ (-), and PTCC۵۲۷۷ (+), The spore suspension was transferred onto CM۱۷ agar plates with different concentrations of acetoacetanilide (۱-۱.۸g/l). After cultivation at ۲۸°C for ۹۶ hr, the colonies were transferred to fresh medium with same concentrations of acetoacetanilide and repeated for ۸ times.RESULTS AND DISCUSSIONDespite the decrease in the biomass of the strains grown in the environment containing the inhibitor compared to the original strain, the amount of beta-carotene produced by this strain in one gram of dry biomass is ۴ times higher than the amount produced in the original strain.The results showed strain with the ability to grow at higher concentrations of this inhibitor can direct more carbon flux to the carotenoid biosynthesis pathway through the intermediary of acetyl-CoA, and thus, it will be effective in the production of β-carotene.CONCLUSIONThis study is expected to contribute to the development of information on the tolerance of molds that regularly exposed to forms of metabolic inhibitors.

کلیدواژه ها:

Blakeslea trispora ، Betacarotene ، inhibitore ، Acetoacetanilide ، Mevalonate