Temperature influences beta-carotene production in recombinant Saccharomyces cerevisiae expressing carotenogenic genes from Phaffia rhodozyma.

摘要

Red yeast Phaffia rhodozyma is a prominent microorganism able to synthesize carotenoid. Here, three carotenogenic cDNAs of P. rhodozyma CGMCC 2.1557, crtE, crtYB and crtI, were cloned and introduced into Saccharomyces cerevisiae INVSc1. The recombinant Sc-EYBI cells could synthesize 258.8 +or- 43.8 mug g-1 dry cell weight (DCW) of beta-carotene when growing at 20 degrees C, about 59-fold higher than in those growing at 30 degrees C. Additional expression of the catalytic domain of 3-hydroxy-3-methylglutaryl-coenzyme A reductase from S. cerevisiae (Sc-EYBIH) increased the beta-carotene level to 528.8 +or- 13.3 mug g-1 DCW as cells growing at 20 degrees C, 27-fold higher than cells growing at 30 degrees C, although cells grew faster at 30 degrees C than at 20 degrees C. Consistent with the much higher beta-carotene level in cells growing at 20 degrees C, transcription level of three crt genes and cHMG1 gene in cells growing at 20 degrees C was a little higher than in those growing at 30 degrees C. Meanwhile, expression of three carotenogenic genes and accumulation of beta-carotene promoted cell growth. These results reveal the influence of temperature on beta-carotene biosynthesis and may be helpful for improving beta-carotene production in recombinant S. cerevisiae