Photo-induced reduction of flavin mononucleotide in aqueous solutions |
| |
Authors: | S-H Song B Dick A Penzkofer |
| |
Institution: | 1. Institut für Physikalische und Theoretische Chemie, Universität Regensburg, 93053 Regensburg, Germany;2. Institut II – Experimentelle und Angewandte Physik, Universität Regensburg, Universitätstrasse 31, D-93053 Regensburg, Germany |
| |
Abstract: | The photo-induced reduction of flavin mononucleotide (FMN) in aqueous solutions is studied by absorption spectra measurement under aerobic and anaerobic conditions. Samples without exogenous reducing agent and with the exogenous reducing agents ethylene-diamine-tetraacetic acid (EDTA) and dithiothreitol (DTT) are investigated. Under anaerobic conditions the photo-induced reduction with and without reducing agents is irreversible. Under aerobic conditions the photo-reduction without added reducing agent is small compared to the photo-degradation, and the photo-reduction of FMN by the reducing agents is reversible (re-oxidation in the dark). During photo-excitation of FMN the dissolved oxygen is consumed by singlet oxygen formation and subsequent chemical reaction. After light switch-off slow re-oxidation (slow absorption recovery) occurs due to air in-diffusion from surface. EDTA degradation by FMN excitation leads to oxygen scavenging. The quantum efficiencies of photo-reduction under aerobic and anaerobic conditions are determined. The re-oxidation of reduced FMN under aerobic conditions and due to air injection is investigated. |
| |
Keywords: | Flavin mononucleotide (FMN) Ethylene-diamine-tetraacetic acid (EDTA) Dithiothreitol (DTT) Flavin photo-reduction Aerobic photo-reduction Anaerobic photo-reduction Absorption spectroscopy Flavin re-oxidation Oxygen scavenging |
本文献已被 ScienceDirect 等数据库收录! |