Abstract
To identify potential applications of nineteen esterases from thermophiles, we mapped their substrate selectivity and enantioselectivity using a library of 50 esters. We measured the selectivities colorimetrically using Quick E, which uses pH indicators to detect hydrolysis and a chromogenic reference compound as an internal control. The substrate selectivity mapping revealed one esterase, E018b, with a strong preference for acetyl esters (14- to 25-fold over hexanoate). The enantioselectivity mapping revealed a number of cases of high enantioselectivity. Thirteen of the 19 esterases showed moderate or better enantioselectivity (>19) toward 1-phenethyl butyrate favoring the (R)-enantiomer and two esterases (E008, E013) showed moderate or better enantioselectivity (>20) toward methyl 2-chloropropionate favoring the (S)-enantiomer. Three esterases (E001, E004, E005) showed high (>46) enantioselectivity toward menthyl acetate favoring the (R)-enantiomer. This rapid mapping of the selectivity simplifies the characterization of new enzymes.
Original language | English (US) |
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Pages (from-to) | 2991-3004 |
Number of pages | 14 |
Journal | Tetrahedron Asymmetry |
Volume | 15 |
Issue number | 18 |
DOIs | |
State | Published - Sep 20 2004 |
Bibliographical note
Funding Information:We thank Andrew Man Fai Liu for setting up the ester library, Kimberly Bull for the initial screening, Siao Li Chuah for additional screening, David Dietrich and Harjap Grewal for confirming the acetyl selectivity of E018b, Krista L. Morley for rechecking some of the selectivity data, David Demirjian (Zuchem, formerly from ThermoGen, Inc., Chicago, IL) for the generous gift of esterases and the Natural Sciences and Engineering Research Council of Canada for financial support.