Ene-reductases and their Applications

Tanja Knaus, Helen S. Toogood, and Nigel S. Scrutton 

Faculty of Life Sciences, Manchester Institute of Biotechnology, University of Manchester, Manchester, UK 

Enoate reductases (EC 1.3.1.31) are flavin-dependent and iron-sulfur-contain-ing proteins found among others in Clostridium species. Members of this NADHrflavin oxidoreductase/NADH oxidase family are distinguished from other ERs due to their high stereospecificity and strict regioselectivity for the reduction of double bonds of monoacids and monoesters, as well as reducing classical substrates such as a,p-unsaturated aldehydes, cyclic ketones, and methyl ketones. However, these enzymes are extremely oxygen sensitive, so they have not been employed in biocatalysis so far [2,3]. 

However, the most extensively investigated class of ERs is members of the OYE family of flavin oxidoreductases (EC 1.6.99.1). There is detailed information known about OYEs, such as their structure, reaction mechanism, substrate scope, kinetic properties, and biocatalytic approaches. Therefore, this chapter will focus on this latter class of enzymes. They have been intensively studied over the past decade in view of their applicability in preparative-scale biotransformations [1, 8-12]. These FMN-containing enzymes catalyze the asymmetric reduction of a,p-unsaturated 

Green Biocatalysis, First Edition. Edited by Ramesh N. Patel. 

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