Patent ID: 8168405

Claim:
A method for detecting or determining the presence or amount of a mutant dehalogenase polypeptide in a sample comprising the steps of: a) providing a sample containing a polypeptide comprising said mutant dehalogenase, wherein the mutant dehalogenase has at least 85% amino acid sequence identity to SEQ ID NO:82 and at least two amino acid substitutions, the mutant dehalogenase being capable of forming a bond with a dehalogenase substrate that is more stable than the bond formed between the dehalogenase of SEQ ID NO:82 and the substrate, wherein one substitution is at a residue corresponding to residue 272 of SEQ ID NO:82, and wherein a second substitution is, or wherein second and third substitutions are, at a residue or residues corresponding to residue 175 and/or residue 176 of SEQ ID NO:82; b) contacting the mutant dehalogenase with a dehalogenase substrate which comprises one or more functional groups; and c) detecting or determining the presence or amount of the functional group, thereby detecting or determining the presence or amount of the polypeptide.