Pichia methanolica

Patel and coworkers reported that microbial reduction of ethyl l-benzyl-3-oxopiperidine-4-carboxylate by Candida parapsilosis SC16 347 gave ethyl cis-(3R,4R)-1 -benzyl-3AMiydro-xypiperidine-4/ -carboxylate as the major product in 97.4% diastereomeric excess (de) and 99.8% ee (Figure 7.2), while 99.5% de and 98.2% ee were achieved in the reduction catalyzed by Pichia methanolica SC16 415 [14]. 

Wang H, Lu F, Sun Y et al (2004) Heterologous expression of lignin peroxidase of Phaner-ochaete chrysosporium in Pichia methanolica. Biotechnol Lett 26 1569-1573... 

Kushnirov VV, Kochneva-Pervukhova N, Chechenova MB, Frolova NS, Ter-Avanesyan MD (2000) Prion properties of the Sup35 protein of yeast Pichia methanolica. EMBO J 19 324-331... 

Both chiral compounds have been prepared by enantioselective reduction of ethyl-5-oxohexanoate 71 and 5-oxohexanenitrile 72 by Pichia methanolica SC 16116. Reaction yields of 80%-90% and more than 95% EEs were obtained for each chiral compound. In an alternate approach, the enzymatic resolution of racemic 5-hydroxy-hexane nitrile 73 by enzymatic succinylation was demonstrated using immobilized lipase PS-30 to obtain (S)-5-hydroxyhexanenitrile 69 in 35% yield (maximum yield is 50%). (S)-5-Acetoxy-hexanenitrile 74 was prepared by enantioselective enzymatic hydrolysis of racemic 5-acetoxyhexanenitrile 75 by Candida antarctica lipase. A reaction yield of 42% and an EE of more than 99% were obtained [96]. 

In an alternate approach, the enantioselective microbial reduction of methyl-4-(2 -acetyl-5 -fluorophenyl) butanoates 80 (Figure 16.19B) was demonstrated using strains of Candida and Pichia. Reaction yields of 40%-53% and EEs of 90%-99% were obtained for the corresponding (5)-hydroxy esters 77. The reductase that catalyzed the enantioselective reduction of ketoesters was purified to homogeneity from cell extracts of Pichia methanolica SC 13825. It was cloned and expressed in E. coli, and recombinant cultures were used for the enantioselective reduction of the keto-methyl ester 80 to the corresponding (5)-hydroxy methyl ester 77. On a preparative scale, a reaction yield of 98% with an EE of 99% was obtained [99]. 

Fig. 4. (A) Synthesis of chiral intermediates for melatonin receptor agonist Enantioselective microbial hydrolysis of racemic epoxide US) to the corresponding (/ )-diol (14) and unreacted (5)-epoxide (12). (B) Stereoinversion of racemic diol (16) to 5-diol (15) by Candida boidinii and Pichia methanolica.

Microbial reduction of ethyl l-benzyl-3-oxo-piperidme-4-carboxylate 19 has been accomplished by a selection of microbes after screening of 91 microorpnisms, and the best results were achieved particularly by Candida parapsilosis and Pichia methanolica [23]. 

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