The gene encoding a putative protein from Candida parapsilosis CDC317 (CPE) was cloned and overexpressed in Escherichia coli. The protein was amenable to overexpression in E. coli and constituted 35% of the total cell protein content. The optimal activity was determined at pH 5.5 and 40 degrees C with the substrate 4-chloro-3-oxobutanoate ethyl ester (COBE). The optical purity of the product was over 99% enantiomeric excess for the (S)-isomer, and the molar conversion yield of the product was 91.1%. The apparent k(m) value for CUBE was 0.19 +/- 0.01 mM, which is an order of magnitude lower than that of other enzymes in the literature. (C) 2012 Elsevier Ltd. All rights reserved.