title: Identification of amino acid residues responsible for high initial luminescence intensity in a calcium-binding photoprotein, clytin-II.
abstract: Clytin-II (CL-II) is an isotype of the calcium-binding photoprotein clytin-I (CL-I) from Clytia gregaria. CL-II shows approximately 4.5-fold higher initial luminescence intensity than CL-I with the same luminescence capacity, and is a potential candidate for a G-protein-coupled receptor assay among photoproteins. To investigate the high initial luminescence intensity of CL-II, the chimeric proteins between CL-I and CL-II were prepared and the responsible amino acid residues in CL-II were identified by site-specific mutagenesis of CL-I. The luminescence properties of CL-I were converted to those of CL-II by the replacement of only four amino acids in CL-I, and these amino acids did not interact with 2-peroxycolenterazine.
authors.affiliation: Yokohama Research Center, JNC Corporation, 5-1 Okawa, Kanazawa-ku, Yokohama 236-8605, Japan. Electronic address: sinouye@jnc-corp.co.jp.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Inouye
authors.affiliation: Yokohama Research Center, JNC Corporation, 5-1 Okawa, Kanazawa-ku, Yokohama 236-8605, Japan.
authors.forename: Yuiko
authors.initials: Y
authors.lastname: Sahara-Miura
mesh_terms: D019943:Amino Acid Substitution; D000596:Amino Acids / Q000737:chemistry*; D001665:Binding Sites; D002135:Calcium-Binding Proteins / Q000737:chemistry*; D008163:Luminescent Measurements / Q000379:methods*; D008164:Luminescent Proteins / Q000737:chemistry*; D011485:Protein Binding; D013329:Structure-Activity Relationship
chemical_list: D000596:Amino Acids; D002135:Calcium-Binding Proteins; D008164:Luminescent Proteins; C046165:phialidin
keywords: Aequorin; Chimeric protein; GPCR reporter assay; Mitochondrial signal peptide; Photoprotein