A conserved START domain coenzyme Q-binding polypeptide is required for efficient Q biosynthesis, respiratory electron transport, and antioxidant function in Saccharomyces cerevisiae.

ABSTRACT: Coenzyme Qn (ubiquinone or Qn) is a redox active lipid composed of a fully substituted benzoquinone ring and a polyisoprenoid tail of n isoprene units. Saccharomyces cerevisiae coq1-coq9 mutants have defects in Q biosynthesis, lack Q6, are respiratory defective, and sensitive to stress imposed by polyunsaturated fatty acids. The hallmark phenotype of the Q-less yeast coq mutants is that respiration in isolated mitochondria can be rescued by the addition of Q2, a soluble Q analog. Yeast coq10 mutants share each of these phenotypes, with the surprising exception that they continue to produce Q6. Structure determination of the Caulobacter crescentus Coq10 homolog (CC1736) revealed a steroidogenic acute regulatory protein-related lipid transfer (START) domain, a hydrophobic tunnel known to bin

SUBMITTER: Allan CM 

PROVIDER: S-EPMC3909687 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature