title: Photodynamic effect of hypericin on the conformation and catalytic activity of hemoglobin.
abstract: Hypericin, extracted from H. perforatum, can induce the generation of reactive oxygen species by visible light irradiation, which may consequently induce the conformational change of hemoglobin. We have not only employed UV-vis spectroscopy to observe the changes of UV-vis spectra of the protein, which reveals the conformational changes of the protein, but also employed electrochemical method to obtain its enhanced peroxidase activity. The photodynamic effect of hypericin on the conformation and catalytic activity of the protein has also been proven to be strongly dependent on the irradiation time, the hypericin concentration and the presence of oxygen. This work is beneficial not only to the fabrication of more sensitive hydrogen peroxide biosensor, but also to the guidance of the usage of this medicinal herb molecule, since the conformational change of the protein and the enhanced peroxidase can be easily obtained only by visible light irradiation on hypericin, the process of which is so common to happen.
authors.affiliation: School of Life Science and Shanghai Key Laboratory of Bio-Energy Crops, Shanghai University, Shanghai 200444, P. R. China.|Department of Biochemistry and National Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, P. R. China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Department of Biochemistry and National Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, P. R. China.
authors.forename: Wenying
authors.initials: W
authors.lastname: Meng
authors.affiliation: Department of Biochemistry and National Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, P. R. China.
authors.forename: Peng
authors.initials: P
authors.lastname: Miao
authors.affiliation: School of Life Science and Shanghai Key Laboratory of Bio-Energy Crops, Shanghai University, Shanghai 200444, P. R. China.
authors.forename: Zhiguo
authors.initials: Z
authors.lastname: Yu
authors.affiliation: School of Life Science and Shanghai Key Laboratory of Bio-Energy Crops, Shanghai University, Shanghai 200444, P. R. China.|Department of Biochemistry and National Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, P. R. China.
authors.forename: Genxi
authors.initials: G
authors.lastname: Li