Abstract: Disclosed are a cocaine esterase mutant and use thereof. The cocaine esterase mutant is obtained by mutating a wildtype cocaine esterase, an amino acid sequence of the wildtype cocaine esterase is shown as SEQ ID No.1, the cocaine esterase mutant is T172R/G173Q/L196C/I301C, or additionally added with V116K point mutation, or additionally added with A51 site mutation, and the A51 site mutation is L, Y, V, F or W. Catalytic efficiency of the cocaine esterase mutant screened on a cocaine toxic metabolite benzoylecgonine is greatly improved compared with that of a wildtype enzyme.

Abstract: The presently-disclosed subject matter describes fusion proteins comprising butyrylcholinesterase (BChE) having an improved production yield and biological half-life and nucleotides encoding the same.

Abstract: The presently-disclosed subject matter includes isolated polypeptides that comprise a butyrylcholinestrase (BChE) polypeptide and a second polypeptide. The BChE polypeptide as well as the second polypeptide can be variants and/or fragments thereof. The presently-disclosed subject matter also includes a pharmaceutical composition that comprises the present isolated polypeptide and a suitable pharmaceutical carrier. Further still, methods are provided for treating cocaine-induced conditions, and comprise administering the isolated polypeptide and/or pharmaceutical compositions thereof to an individual.