We propose to determine the metabolic role of alpha-tocopherolquinol in bacteria and animals. We hope to isolate and characterize cis-9,trans-11-octadecadienoate reductase, an enzyme in the anaerobe Butyrivibrio fibrisolvens that uses alpha-tocopherolquinol as an endogenous electron donor. Since alpha-tocopherolquinone can be synthesized in Escherichia coli and animals and can be reduced to alpha-tocopherolquinol, we postulate it plays an oxidation-reduction role in these organisms. We hope to elucidate this role by identifying an end product that requires it for synthesis in bacteria or a compound in animal extracts that can oxidize it under anaerobic conditions. We then plan to elaborate the role of alpha-tocopherolquinol in these metabolic reactions. Included in this aspect is a study of the biochemical mechanism for its reduction by NADH in both animals and bacteria. We also plan to elucidate the biosynthetic pathway of alpha-tocopherolquinone in bacteria and animals. Finally, we plan to determine the biochemical mechanism by which B. fibrisolvens converts alpha-tocopherolquinol to 2-(3,7,11,15-tetramethylhexadecyl)-3,5,6-trimethylbenzoquinol, a compound also found in bacteria.
