Dataset Information

Improving CoQ10 productivity by strengthening glucose transmembrane of Rhodobacter sphaeroides

ABSTRACT:

Background

Several Rhodobacter sphaeroides have been widely applied in commercial CoQ10 production, but they have poor glucose use. Strategies for enhancing glucose use have been widely exploited in R. sphaeroides. Nevertheless, little research has focused on the role of glucose transmembrane in the improvement of production.

Results

There are two potential glucose transmembrane pathways in R. sphaeroides ATCC 17023: the fructose specific-phosphotransferase system (PTSFru, fruAB) and non-PTS that relied on glucokinase (glk). fruAB mutation revealed two effects on bacterial growth: inhibition at the early cultivation phase (12–24 h) and promotion since 36 h. Glucose metabolism showed a corresponding change in characteristic vs. the growth. For ΔfruAΔfruB, maximum biomass (Biomax) was increased by 44.39% and the CoQ10 content was 27.08% more than that of the WT. glk mutation caused a significant decrease in growth and glucose metabolism. Over-expressing a galactose:H+ symporter (galP) in the ΔfruAΔfruB relieved the inhibition and enhanced the growth further. Finally, a mutant with rapid growth and high CoQ10 titer was constructed (ΔfruAΔfruB/tac::galPOP) using several glucose metabolism modifications and was verified by fermentation in 1 L fermenters.

Conclusions

The PTSFru mutation revealed two effects on bacterial growth: inhibition at the early cultivation phase and promotion later. Additionally, biomass yield to glucose (Yb/glc) and CoQ10 synthesis can be promoted using fruAB mutation, and glk plays a key role in glucose metabolism. Strengthening glucose transmembrane via non-PTS improves the productivity of CoQ10 fermentation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12934-021-01695-z.

SUBMITTER: Yang Y

PROVIDER: S-EPMC8557541 | biostudies-literature |

REPOSITORIES: biostudies-literature

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