9: Miscellaneous Biocatalysts

This chapter covers enzyme classes that do not fall into any of the previous chapters, including mandelate racemases, hydantoin racemases, amino acid racemases, carbohydrate isomerases and cis–trans isomerases. The chapter is divided into separate sections, each detailing the transformation carried out by a specific enzyme class. Each section begins with a review of chemical methods of carrying out similar transformations, followed by a description of the enzyme class itself. The substrate scope of each enzyme class, including its chemo-, regio- and stereoselectivity, is discussed and a general mechanism for the enzyme-catalysed reaction is presented where appropriate. This should give the reader an understanding of when and how to use these enzymes.