|FOSTER, JUSTIN - Children'S Nutrition Research Center (CNRC)|
Submitted to: FEBS Letters
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/18/2013
Publication Date: 1/3/2014
Citation: Foster, J., Nakata, P.A. 2014. An oxalyl-CoA synthetase is important for oxalate metabolism in Saccharomyces cerevisiae. FEBS Letters. 588:160-166.
Interpretive Summary: Plant scientists have been avidly working to discover new strategies to increase crop resistance to oxalate-secreting fungal pathogens. These fungal pathogens produce oxalate as a plant toxin that is required by the fungus for plant infection. Such fungi are responsible for major crop losses each year. In this study we report the discovery of an oxalyl-CoA synthetase from yeast which is the first enzyme in a novel pathway of oxalate degradation. Biochemical analysis showed that this enzyme converted oxalate into oxalyl-CoA which is ultimately degraded to CO2. Biological analysis revealed that this enzyme and pathway of oxalate degradation helps protect yeasts from the harmful effects of oxalate that is secreted by other bacterial and fungal microbes present in the environment. Thus, the identification and isolation of this enzyme is an important advancement in our understanding of oxalate metabolism. It also provides us with a potential new strategy, through the expression of this enzyme in plants, to help protect crop plants from oxalate-secreting phytopathogens.
Technical Abstract: Although oxalic acid is common in nature, our understanding of the mechanism(s) regulating its turnover remains incomplete. In this study we identify Saccharomyces cerevisiae acyl-activating enzyme 3 (ScAAE3) as an enzyme capable of catalyzing the conversion of oxalate to oxalyl-CoA. Based on our findings we propose that ScAAE3 catalyzes the first step in a novel pathway of oxalate degradation to protect the cell against the harmful effects of oxalate that is derived from an endogenous process or an environmental source.