Endogenous synthesis of coenzyme Q in eukaryotes

Abstract

Coenzyme Q (Q) functions in the mitochondrial respiratory chain and serves as a lipophilic antioxidant. There is increasing interest in the use of Q as a nutritional supplement. Although the physiological significance of Q is extensively investigated in eukaryotes, ranging from yeast to human, the eukaryotic Q biosynthesis pathway is best characterized in the budding yeast Saccharomyces cerevisiae. At least ten genes (COQ1-COQ10) have been shown to be required for Q biosynthesis and function in respiration. This review highlights recent knowledge about the endogenous synthesis of Q in eukaryotes, with emphasis on S. cerevisiae as a model system.

Identification of Coq11, a New Coenzyme Q Biosynthetic Protein in the CoQ-Synthome in Saccharomyces cerevisiae

“…13 C 6 -Q synthesized de novo from 13 C 6 -4HB in CNAP6 and 13 C 6 -Q synthesized de novo from 13 C 6 -pABA in CNAP9 were not significantly different compared with wild type. 13 synthesized de novo from 13 C 6 -pABA in CNAP6 was higher than wild type, and 13 C 6 -Q synthesized de novo from 13 C 6 -4HB in CNAP9 was lower than wild type. The coq8⌬ strain did not produce detectable de novo 13 C 6 -Q 6 .…”

“…COQ1-COQ9 were identified as complementation groups of Q-deficient yeast mutants (10,11), whereas YAH1 and ARH1 were identified through lipid analysis of Yah1-and Arh1-depleted strains under control of galactose-inducible promoters (12). Deletion of any of these COQ genes results in a loss of Q synthesis and consequently a failure to respire and grow on a nonfermentable carbon source (12,13). Deletion of either YAH1 or ARH1 results in a loss in viability because the biosynthesis of iron-sulfur clusters and heme A requires these gene products (14 -18).…”

Coenzyme Q protects Caenorhabditis elegans GABA neurons from calcium-dependent degeneration

“…COQ-1 catalyzes the first step in Coenzyme Q synthesis, the assembly of the lipophillic polyisoprenoid tail (18). RNAi knockdown of coq-1 is reported to induce uncoordinated (Unc) and Egg-laying defective (Egl) phenotypes, but the mechanism of these effects has not been studied (19).…”

Coenzyme Q supplementation or Over-Expression of the Yeast Coq8 Putative Kinase Stabilizes Multi-Subunit Coq Polypeptide Complexes in Yeast Coq Null Mutants

“…6B). [12,26,37,50,69]. We were able to rescue the growth of each of the coq1-coq9 null mutants on YPEG medium containing ethanol and glycerol as non-fermentable carbon sources, with the addition of 2 µM Q 6 to the medium (data not shown).…”

“…1) [12][13][14]. Yeast mutants lacking any of the Coq1-Coq9 polypeptides are respiratory deficient due to the lack of Q.…”