Production of Coenzyme Q by microbes: an update.

Coenzyme Q (CoQ) is the main CoQ species in human and is used extensively in food, cosmetic and medicine industries because of its antioxidant properties and its benefit in prophylactic medicine and therapy for a variety of diseases. Among various approaches to increase the production of CoQ, microbial fermentation is the most effective. As knowledge of the biosynthetic enzymes and regulatory mechanisms modulating CoQ production increases, opportunities arise for metabolic engineering of CoQ in microbial hosts. In this review, we present various strategies used up to date to improve CoQ production and focus on metabolic engineering of CoQ overproduction in microbes. General strategies of metabolic engineering include providing sufficient precursors for CoQ, increasing metabolic fluxes, and expanding storage capacity for CoQ. Based on these strategies, CoQ production has been significantly improved in natural CoQ producers, as well as in heterologous hosts.