Reductases aldehyde reductase

Many aldehyde reductases transform both aldehydes and ketones. For example, phenylacetaldehyde reductase (PAR) from a styrene-assimilating Corynebacterium strain, ST-10, reduces hexyl aldehyde and phenylacetaldehyde [22aj. Other aldehyde reductases such as one from Sporobolomyces salmonicolor also reduce aldehydes as well as ketones [22b]. 

Itoh N, R Morihama, J Wang, K Okada, N Mizuguchi (1997) Purification and characterization of phenylacet-aldehyde reductase from a styrene-assimilating Corynebacterium strain, STIO. Appl Environ Microbiol 63 3783-3788. 

Kita, K., Nakase, K.-i., Yanase, H. et al. (1999) Purification and characterization of new aldehyde reductases from Sporobolomyces salmonicolor AKU4429. Journal of Molecular Catalysis B-Enzymatic, 6 (3), 305-313. 

Aldehyde dehydrogenase Aldehyde reductase Ketone reductases... 

Aldehyde reductases are a group of isoenzymes that catalyze the NADPH-specific reduction of aldehydes. Ketones do not serve as substrates for these enzymes. The best substrates for aldehyde reductase are aromatic aldehydes and those aldehydes obtained through metabolism of biogenic amines. The species distribution, specificity, and inhibition of aldehyde reductases have been reviewed (792). 

As with the aldehyde reductases, ketone reductases are specific for NADPH as reductant. Also, some isoenzymes of ketone reductase have not been purified to homogeneity and therefore not fully characterized. It is clear, however, that the ketone reductases catalyze reduction of aromatic, aliphatic, cyclic, and unsaturated ketones to the corresponding alcohols. The ketone reductases also catalyze reduction of aromatic and aliphatic aldehydes to primary alcohols. The distribution and specificity of ketone reductases has been reviewed (103). 

Schaller M, Schaffhauser M, Sans N, et al. Cloning and expression of succinic semialdehyde reductase from human brain. Identity with aflatoxin B1 aldehyde reductase. Eur J Biochem 1999 265(3) 1056-1060. 

Ohara H, Miyabe Y, DeyashiM Y, et al. Reduction of drug ketones by dihydrodiol dehydrogenases, carbonyl reductase and aldehyde reductase of human liver. Biochem Pharmacol 1995 50(2) 221-227. 

Harmala alkaloids are inhibitors of brain MAO. Harmane inhibits MAOA in the submicromolar range (5 X 10-7 M) and MAOB in the micromolar range (5 x 10-6 M) (Glover et al. 1982). Harmine inhibits MAOA, but also has additional unspecified monoamine modulatory effects (Meneguz et al. 1994 Fernandez de Arriba et al. 1994). Harmaline or its metabolites may also stimulate aldehyde reductase or catechol 0-methyltransferase (COMT) (Okonmah et al. 1988). 

Most of the vanillic acid was reduced by E. coli containing Car in 2 h to vanillin (80 %) and vanillyl alcohol (20 %). Car does not reduce aldehydes to alcohols. However, E. coli s endogenous aldehyde reductase/dehydrogenase reduces vanillin to vanillyl alcohol. The broad substrate specificity of Car enables the wide application of this biocatalyst to other important applications, such as enantiomeric resolution of isomers such as ibuprofen and the reductions of many other natural and synthetic carboxylic acids. 

Table 2. Properties of aldehyde reductase (AR) of S. salmonicolor and carbonyl reductase (CR) of C. magnoliae...

Fig. 6. Outline of the stereospecific reduction of CAAE by aldehyde reductase (AR) with glucose dehydrogenase (GDH) as the cofactor regenerator in an organic solvent-water two-phase system...

Cytochrome P450 monooxygenase Azo and nitro group reductase Aldehyde dehydrogenase... 

Other enzymes may also be similarly inactivated by such cyclopropanone adducts generated in situ by catalytic unravelling of some latent precursors. NAD+ as coenzyme favours the electrophilic attack of AGP 17 on the enzymic thiol group, and considerably increases the rate of inhibition [17]. ALDH in brain was also inhibited in rats pretreated with coprine, and aldehyde reductase was slightly inhibited by AGP 17, in vitro [22]. 

This enzyme [EC 1.1.1.21], also known as aldehyde reductase and polyol dehydrogenase (NADP ), catalyzes the reaction of an alditol with NAD(P) to generate an aldose and NAD(P)H. The enzyme exhibits a broad specificity for the alditol. 

PHYSICAL ORGANIC CHEMISTRY NOMENCLATURE ALDEHYDE DEHYDROGENASE ALDEHYDE HYDRATION ALDEHYDE OXIDASE ALDEHYDE OXIDOREDUCTASE ALDOSE REDUCTASE Aldehyde reduction to alcohols, BOROHYDRIDE REDUCTION ALDOLASE Aldolase reduction,... 

El-Kabbani O, Green NC, Lin G, Carson M, Narayanam SVL, Moore K, Flynn TG, DeLucas LJ. Structures of human and porcine aldehyde reductase an enzyme implicated in diabetic complications. Acta CrystallogrD 1994 50 859-868. 

El-Kabbani O, Judge K, Ginell SL, Myles Daa, DeLucas LJ, Flynn TG. Structure of porcine aldehyde reductase holoenzyme. Nat Struct Biol 1995 2 687-692. 

It is well-known that plants do not synthesize vitamin A. Also, animals can only synthesize vitamin A from p-carotene or carotenoids in which one-half of the molecule is like p-carotene. In nature, the vitamin A precursor comes either from plants or microorganisms. The most common sources of vitamin A in citrus are a- and p-carotenes and p-cryptoxanthin. In addition to the above name carotenoids, p-apo-8 -carotenal in citrus peel could be a source of provitamin A. However, the peel is not usually consumed. Provitamin A compounds are cleaved to form vitamin A aldehyde in the intestine by p-carotene 15,15 -oxygenase (Figure 4) (54). Aldehyde reductase reduces the aldehyde to the all trans-vitamin A. p-Carotene is cleaved between the 15,15 carbon... 

M. Wada, K. Kita, H. Yanase, and S. Shimizu, Stereoselective reduction of of ethyl 4-chloro-3-oxobutanoate by Escherichia coli transformant cells coexpressing the aldehyde reductase and glucose dehydrogenase genes, Appl. Microbiol. Biotechnol. 1999, 53, 486-490. 

Ketone and Aldehyde Reduction. In addition to the reduction of aldehyde and ketones through the reverse reaction of alcohol dehydrogenase, a family of aldehyde reductases also reduces these compounds. These reductases are NADPH-dependent, cytoplasmic enzymes of low molecular weight and have been found in liver, brain, kidney, and other tissues. 

Application of Aldehyde Reductase to the Production of Chiral Building Blocks... 

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