Reduction of Aldehydes and Ketones Using Whole Cells

3 Reduction of Aldehydes and Ketones Using Whole Cells 

However, these distinct advantages have to be taken into consideration alongside some significant drawbacks  

On the one hand, a substrate may be reduced by a single oxidoreductase via transition states for the two enantiomers (or the enantiotopic faces) which have similar values of free energy. In other words, inefficient chiral recognition takes place allowing an alternative fit of the substrate within a single enzyme. 

If two enzymes, each with high but opposite stereochemical preference, compete for the same substrate, the optical purity of the product is determined by the relative rates of the individual reactions. The latter, in turn, depend on the substrate concentration for the following reasons At concentrations below saturation, the relative rates are determined by the ratio for each enzyme. On 

The following general techniques can be applied to enhance the selectivity of 

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