Rhodococcus alcohol dehydrogenases

Figure 8.3 Reduction of ketone with alcohol dehydrogenase from Rhodococcus erythropolis using formate as a hydrogen source [4a].

An (5)-specific alcohol dehydrogenase gene from Rhodococcus erythropolis and GDH from Bacillus subtilis were ligated into one plasmid, which was expressed in Escherichia coli strain DSM14 459 to provide an (S)-selective whole-cell catalyst. 

The reduction of several ketones, which were transformed by the wild-type lyophilized cells of Rhodococcus ruber DSM 44541 with moderate stereoselectivity, was reinvestigated employing lyophilized cells of Escherichia coli containing the overexpressed alcohol dehydrogenase (ADH- A ) from Rhodococcus ruber DSM 44541. The recombinant whole-cell biocatalyst significantly increased the activity and enantioselectivity [41]. For example, the enantiomeric excess of (R)-2-chloro-l-phenylethanol increased from 43 to >99%. This study clearly demonstrated the advantages of the recombinant whole cell biocatalysts over the wild-type whole cells. 

US5846813 [48] desulfurization of DBT by Rhodococcus Sp. IGTS8. biodesulfurization of a fossil fuel by adding to the biocatalytic aqueous phase a nicotinamide adenosine dinucleotide and an additional amount of a group III alcohol dehydrogenase. Incubation and separation follows the mixing step. 

Recently, we adopted the same system for the reduction of 4-phenyl-2-butanone to (S)-4-phenyl-2-butanol using the NADH-dependent horse liver alcohol dehydrogenase (HLADH) and S-ADH from Rhodococcus sp [68] with high enantioselectivity (Fig. 17) [69]. As mediator, we applied the low-molecular... 

The chiral compounds (/ )- and (5)-bis(trifluoromethyl)phenylethanol are particularly useful synthetic intermediates for the pharmaceutical industry, as the alcohol functionality can be easily transformed without a loss of stereospecificity and biological activity, and the trifluoromethyl functionalities slow the degradation of the compound by human metabolism. A very efficient process was recently demonstrated for the production of the (5)-enantiomer at >99% ee through ketone reduction catalyzed by the commercially available isolated alcohol dehydrogenase enzyme from Rhodococcus erythropolis (Figure 9.1). The (7 )-enantiomer could be generated at >99% ee as well using the isolated ketone reductase enzyme KRED-101. 

New Alcohol Dehydrogenases from Strains of Rhodococcus and Lactobacillus... 

Fig. 3.43 6-Methyl-hept-5-en-2-one reduction and simultaneous NAD+ regeneration using alcohol dehydrogenase from Rhodococcus rubber.

Alcohol Dehydrogenase Origin Rhodococcus erythropolis Julich Enzyme Products... 

YADH and HLADH are less useful for the asymmetric reductirai of open-chain ketones, but this gap is efficiently covered by a range of alcohol dehydrogenases from mesophiUc bacteria, such as Rhodococcus (ADH-A) and Lactobacillus (LBADH, LKADH), and thermophilic Thermoanaerobacter [802] and Thermo-anaerobium (TBADH) strains (Scheme 2.119) [296, 803-806]. Some of these enzymes are remarkably thermostable (up to 85°C) and can tolerate the presence of organic solvents such as /sopropanol, which serves as hydrogen-donor for NADP-recycling in a coupled-substrate approach [807-809]. 

Abokitse, K. and Hummel, W. (2003) Cloning, sequence analysis, and heterologous expression of the gene encoding a (S)-specific alcohol dehydrogenase from Rhodococcus erythropolis DSM 43297. Appl. Microbiol. Biotech-nol, 62 (4), 380-386. 

S)-l-[3,5-Bis(trifluoromethyl)phenyl]ethanol (28, Figure 4.5) is an important intermediate for the synthesis of NK-1 receptor antagonists. Pollard and coworkers used alcohol dehydrogenase from Rhodococcus erythropolis and formate dehydrogenase to recycle NADH [57] and obtain this enantiopure alcohol. Under optimized conditions, the process could be scaled-up at 25 kg at 30 °C with a high substrate concentration (100 g/1) affording a space-time yield of 100-110 g/1 per day. 

Karabec, M., Lyskowski, A., Tauber, K.C., Steinkellner, G., Kroutil, W., Grogan, G., and Gruber, K. (2010) Structural insights into substrate specificity and solvent tolerance in alcohol dehydrogenase ADH- A from Rhodococcus ruber... 

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