Nitrile as Activating Group in the Asymmetric Bioreduction of β-Cyanoacrylic Acids Catalyzed by Ene-Reductases.

Asymmetric bioreduction of an ()-β-cyano-2,4-dienoic acid derivative by ene-reductases allowed a shortened access to a precursor of pregabalin [()-3-(aminomethyl)-5-methylhexanoic acid] possessing the desired configuration in up to 94% conversion and >99% . Deuterium labelling studies showed that the nitrile moiety was the preferred activating/anchor group in the active site of the enzyme over the carboxylic acid or the corresponding methyl ester.

Influence of phosphocholine alkyl chain length on peptide-micelle interactions and micellar size and shape.

The interaction with biological membranes is of functional importance for many peptides and proteins. Structural studies on such membrane-bound biomacromolecules are often carried out in solutions containing small membrane-mimetic assemblies of detergent molecules. To investigate the influence of the hydrophobic chain length on the structure, diffusional and dynamical behavior of a peptide bound to micelles, we studied the binding of three peptides to n-phosphocholines with n ranging from 8 to 16.

Stereoselectivities of microbial epoxide hydrolases.

Epoxide hydrolases from bacterial and fungal sources are highly versatile biocatalysts for the asymmetric hydrolysis of epoxides on a preparative scale. Besides kinetic resolution, which yields the corresponding enantiomerically enriched vicinal diol and the remaining nonconverted epoxide, enantioconvergent processes are also possible, which lead to the formation of a single enantiomeric diol from a racemic oxirane. The data available to date indicate that the enantioselectivities of enzymes from certain microbial sources can be correlated to the substitutional pattern of various types of substrates: red yeasts (e.