Relationship Between Coenzyme Q 10 Synthesis and Cytochrome Accumulation in Rhodobacter sphaeroides 2.4.1

To find the relationship between CoQ10 synthesis and cytochrome accumulation in R. sphaeroides 2.4.1, we constructed two mutants (△prrA and △ppsR). ppsR mutation apparently activated cytochrome synthesis under aerobic cultivation, while prrA defection obviously inhibited the synthesis of cytochrome. Aerobic CoQ10 fermentation revealed △prrA growth was repressed after culturing for 24 h and the final biomass accumulated was reduced by 15.6%. Simultaneously, the final CoQ10 yield was reduced to 36 ± 0.58 mg/L which was only 85.7% as that of the WT. Also, both the bacterial growth and the CoQ10 yield of △ppsR were decreased. In the aspect of CoQ10 content, the result showed different phenomena that CoQ10 content for △prrA was increased, while for △ppsR was reduced. The result further supposed cytochrome accumulation competed with the CoQ10 synthesis in common precursor.