Patent ID: 8399616

Claim:
A fusion protein comprising: (1) a first region selected from the group consisting of (a) to (d) below: (a) a region consisting of the amino acid sequence of SEQ ID NO: 18; (b) a region consisting of the amino acid sequence of SEQ ID NO: 18 wherein 1 to 10 amino acids are deleted, substituted, inserted and/or added and having a catalytic ability for a luminescence activity with a luciferin which is a substrate; (c) a region consisting of an amino acid sequence having at least 90% homology to the amino acid sequence of SEQ ID NO: 18 and having a catalytic ability for a luminescence activity with a luciferin which is a substrate; and, (d) a region consisting of an amino acid sequence encoded by a polynucleotide which hybridizes under high stringent conditions to a polynucleotide consisting of a nucleotide sequence complementary to the nucleotide sequence of SEQ ID NO: 17 and having a catalytic ability for a luminescence activity with a luciferin which is a substrate, wherein the high stringent conditions are 5×SSC, 5× Denhardt's solution, 0.5% (w/v) SDS, 50% (v/v) formamide and 50° C.; and, (2) a second region consisting of an amino acid sequence for a polypeptide having at least one cysteine residue for binding to other useful compound via its thiol group, wherein the second region is selected from the group consisting of (e) to (h) below: (e) a region consisting of the amino acid sequence of SEQ ID NO: 20; (f) a region comprising the amino acid sequence of SEQ ID NO: 20 wherein 1 to 3 amino acids are deleted, substituted, inserted and/or added and having at least one cysteine residue for binding to other useful compound via the thiol group; (g) a region comprising an amino acid sequence having at least 90% homology to the amino acid sequence of SEQ ID NO: 20 and having at least one cysteine residue for binding to other useful compound via the thiol group; and, (h) a region comprising an amino acid sequence encoded by a polynucleotide which hybridizes under high stringent conditions to a polynucleotide consisting of a nucleotide sequence complementary to the nucleotide sequence of SEQ ID NO: 19 and having at least one cysteine residue for binding to other useful compound via the thiol group, wherein the high stringent conditions are 5×SSC, 5× Denhardt's solution, 0.5% (w/v) SDS, 50% (v/v) formamide and 50° C.