title: Long-term chemiluminescence signal is produced in the course of luminol oxidation catalyzed by enhancer-independent peroxidase purified from Jatropha curcas leaves.
abstract: Isoenzyme c of horseradish peroxidase (HRP-C) is widely used in enzyme immunoassay combined with chemiluminescence (CL) detection. For this application, HRP-C activity measurement is usually based on luminol oxidation in the presence of hydrogen peroxide (H2O2). However, this catalysis reaction was enhancer dependent. In this study, we demonstrated that Jatropha curcas peroxidase (JcGP1) showed high efficiency in catalyzing luminol oxidation in the presence of H2O2. Compared with HRP-C, the JcGP1-induced reaction was enhancer independent, which made the enzyme-linked immunosorbent assay (ELISA) simpler. In addition, the JcGP1 catalyzed reaction showed a long-term stable CL signal. We optimized the conditions for JcGP1 catalysis and determined the favorable conditions as follows: 50 mM Tris buffer (pH 8.2) containing 10 mM H2 O2, 14 mM luminol and 0.75 M NaCl. The optimum catalysis temperature was 30°C. The detection limit of JcGP1 under optimum condition was 0.2 pM. Long-term stable CL signal combined with enhancer-independent property indicated that JcGP1 might be a valuable candidate peroxidase for clinical diagnosis and enzyme immunoassay with CL detection.
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China.
authors.forename: Peipei
authors.initials: P
authors.lastname: Duan
authors.affiliation: Chengdu Institute of Biological Products Co., Ltd., Chengdu, 610021, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Cai
authors.affiliation: Key Laboratory of Protein and Peptide Pharmaceutical, CAS-University of Tokyo Joint Laboratory of Structural Virology and Immunology, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Beijing, 100101, China.
authors.forename: Yongting
authors.initials: Y
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China.
authors.forename: Yangxi
authors.initials: Y
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China.
authors.forename: Shujuan
authors.initials: S
authors.lastname: Zou
mesh_terms: D002384:Catalysis; D006735:Horseradish Peroxidase / Q000737:chemistry / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000737:chemistry; D031286:Jatropha / Q000201:enzymology*; D007700:Kinetics; D057230:Limit of Detection; D049449:Luminescence; D008163:Luminescent Measurements / Q000379:methods*; D008165:Luminol / Q000737:chemistry*; D010084:Oxidation-Reduction; D009195:Peroxidase / Q000737:chemistry* / Q000378:metabolism; D018515:Plant Leaves / Q000201:enzymology; D013696:Temperature
chemical_list: D008165:Luminol; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase; D009195:Peroxidase
keywords: Jatropha curcas; chemiluminescence; luminol; peroxidase