The damage and tolerance mechanisms of Phaffia rhodozyma mutant strain MK19 grown at 28 °C

Abstract Background Phaffia rhodozyma has many desirable properties for astaxanthin production, including rapid heterotrophic metabolism and high cell densities in fermenter culture. The low optimal temperature range (17–21 °C) growth synthesis this species presents an obstacle to efficient industrial-scale production. inhibition mechanism of at > 21 °C P. have not been investigated. Results MK19, a mutant strain grows well moderate temperatures, its was also inhibited 28 °C, but such mitigated, biomass 6 g/L obtained after 100 h Transcriptome analysis indicated that resulted from strong suppression DNA RNA MK19. Growth due membrane damage with characteristic mRNA content fatty acid (f.a.) pathway transcripts ( acc , fas 1, 2), consequent f.a. content. Thinning wall mannose (leading loss integrity) contributed reduced Levels ergosterol, two end-products isoprenoid biosynthesis (a shunt biosynthesis), reached 2000 µg/g 7500 respectively; ~2-fold higher than levels or 25 °C. Abundance important component, compensated lack f.a., making possible the production MK19 Conclusions Inhibition results blocking DNA, RNA, biosynthesis. In abundant ergosterol made Significant accumulation active MVA Strengthening can be feasible metabolic engineering approach enhancement . present findings provide useful mechanistic insights regarding adaptation improved understanding techniques industrial scale by economically yeast species.