Patent ID: 8318156

Claim:
An isolated mutant cocaine esterase (CocE) polypeptide comprising an amino acid sequence at least 95% identical to SEQ ID NO: 1 having at least one substitution, addition or deletion, wherein the at least one substitution, addition or deletion is selected from the group consisting of L163V; V225I; I218L; A310D; A149S; S159A; S265A; S56G; W220A; S140A; F189L; A193D; T254R; N42V; V262L; L508G; Y152H; V160A; T172R; Y532F; T74S; W285T; L146P; D533S; A194R; G173Q; C477T; K531A; R41I; L119A; K46A; F84Y; T172R-G173Q; L169K; F189A; N197K; R182K; F189K; V190K; Q191K; A194K; I175-G-G-A186; and T176-G-G-D185; and the mutant CocE polypeptide has esterase activity with increased thermostability at 37° C. as compared to wild-type CocE having the amino acid sequence of SEQ ID NO:1.