Horse hver alcohol dehydrogenase

The two oxidoreductase systems most frequentiy used for preparation of chiral synthons include baker s yeast and horse hver alcohol dehydrogenase (HLAD). The use of baker s yeast has been recendy reviewed in great detail (6,163) and therefore will not be coveted here. The emphasis here is on dehydrogenase-catalyzed oxidation and reduction of alcohols, ketones, and keto acid, oxidations at unsaturated carbon, and Bayer-Vidiger oxidations. 

Virto, C., Svensson, L, Adlercreutz, P., and Mattiasson, B., Catalytic activity of noncovalent complexes of horse hver alcohol dehydrogenase, NAD+, and polymers, dissolved or suspended in organic solvents, BiotechnoL Lett., 17, 877-882, 1995. 

The first example of reaction of a half sandwich metallocene with a protein was reported a few years later. Tetramethylcyclobutadiene nickel(II) dichloride 2 was shown to react with the enzyme horse hver alcohol dehydrogenase to afford a modified enzyme devoid of zinc and enzymatic activity and containing 8 mol nickel per mol protein. The mode of binding of this organometallic complex had not been fully elucidated at that time but was thought to occur by substitution of the chloride ligands by nucleophilic residues [3],... 

Alcohol dehydrogenase-catalyzed reduction of ketones is a convenient method for the production of chiral alcohols. HLAD, the most thoroughly studied enzyme, has a broad substrate specificity and accommodates a variety of substrates (Table 11). It efficiendy reduces all simple four- to nine-membered cycHc ketones and also symmetrical and racemic cis- and trans-decalindiones (167). Asymmetric reduction of aUphatic acycHc ketones (C-4—C-10) (103,104) can be efficiendy achieved by alcohol dehydrogenase isolated from Thermoanaerohium hrockii (TBADH) (168). The enzyme is remarkably stable at temperatures up to 85°C and exhibits high tolerance toward organic solvents. Alcohol dehydrogenases from horse Hver and T. hrockii... 

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