74075-00-6Relevant articles and documents
A genome-wide screen in Escherichia coli reveals that ubiquinone is a key antioxidant for metabolism of long-chain fatty acids
Agrawal, Shashank,Jaswal, Kanchan,Shiver, Anthony L.,Balecha, Himanshi,Patra, Tapas,Chaba, Rachna
, p. 20086 - 20099 (2017)
Long-chain fatty acids (LCFAs) are used as a rich source of metabolic energy by several bacteria including important pathogens. Because LCFAs also induce oxidative stress, which may be detrimental to bacterial growth, it is imperative to understand the strategies employed by bacteria to counteract such stresses. Here, we performed a genetic screen in Escherichia coli on the LCFA, oleate, and compared our results with published genomewide screens of multiple non-fermentable carbon sources. This large-scale analysis revealed that among components of the aerobic electron transport chain (ETC), only genes involved in the biosynthesis of ubiquinone, an electron carrier in the ETC, are highly required for growth in LCFAs when compared with other carbon sources. Using genetic and biochemical approaches, we show that this increased requirement of ubiquinone is to mitigate elevated levels of reactive oxygen species generated by LCFA degradation. Intriguingly, we find that unlike other ETC components whose requirement for growth is inversely correlated with the energy yield of non-fermentable carbon sources, the requirement of ubiquinone correlates with oxidative stress. Our results therefore suggest that a mechanism in addition to the known electron carrier function of ubiquinone is required to explain its antioxidant role in LCFA metabolism. Importantly, among the various oxidative stress combat players in E. coli, ubiquinone acts as the cell's first line of defense against LCFAinduced oxidative stress. Taken together, our results emphasize that ubiquinone is a key antioxidant during LCFA metabolism and therefore provides a rationale for investigating its role in LCFA-utilizing pathogenic bacteria.
METHOD OF STABILIZING REDUCED COENZYME Q sb 10 /sb
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Page/Page column 17, (2008/06/13)
The present invention provides a stabilization method, a preservation method and the like method of reduced coenzyme Q10, which is useful as functional nutritive foods, specific health foods and the like. Furthermore, the present invention provides a method for efficiently obtaining reduced coenzyme Q10 of high quality and by a method suitable for a commercial production. It is possible to handle and stably preserve reduced coenzyme Q10 under a condition that oxidation by a molecular oxygen is inhibited by contacting reduced coenzyme Q10 with an ascorbic acid and citric acid or a related compound thereof, and thus a stabilized composition is obtained. Moreover, reduced coenzyme Q10 is converted into a crystalline state in such a condition that the formation of oxidized coenzyme Q10 as a byproduct is minimized by crystallizing reduced coenzyme Q10 in the presence of ascorbic acid or a related compound thereof, etc., and thus a reduced coenzyme Q10 crystal of high quality is produced. Furthermore, by successively crystallizing the generated reduced coenzyme Q10 in the presence of ascorbic acid or a related compound thereof after reducing oxidized coenzyme Q10 to reduced coenzyme Q10 using ascorbic acid or a related compound thereof, operations are simplified and minimized, and thus reduced coenzyme Q10 of high quality is produced.
