Functional Characterization of Salt-Tolerant Microbial Esterase WDEst17 and Its Use in the Generation of Optically Pure Ethyl (R)-3-hydroxybutyrate

Yilong Wang, Yongkai Xu, Yun Zhang, Aijun Sun, Yunfeng Hu

Chirality. 2018 Jun;30(6):769-776.

PMID: 29573466

Abstract:

The two enantiomers of ethyl 3-hydroxybutyrate are important intermediates for the synthesis of a great variety of valuable chiral drugs. The preparation of chiral drug intermediates through kinetic resolution reactions catalyzed by esterases/lipases has been demonstrated to be an efficient and environmentally friendly method. We previously functionally characterized microbial esterase PHE21 and used PHE21 as a biocatalyst to generate optically pure ethyl (S)-3-hydroxybutyrate. Herein, we also functionally characterized one novel salt-tolerant microbial esterase WDEst17 from the genome of Dactylosporangium aurantiacum subsp. Hamdenensis NRRL 18085. Esterase WDEst17 was further developed as an efficient biocatalyst to generate (R)-3-hydroxybutyrate, an important chiral drug intermediate, with the enantiomeric excess being 99% and the conversion rate being 65.05%, respectively, after process optimization. Notably, the enantio-selectivity of esterase WDEst17 was opposite than that of esterase PHE21. The identification of esterases WDEst17 and PHE21 through genome mining of microorganisms provides useful biocatalysts for the preparation of valuable chiral drug intermediates.

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
AP5405414	Ethyl 3-hydroxybutyrate		5405-41-4	Price