Messiha Hanan L, Wongnate Thanyaporn, Chaiyen Pimchai, Jones Alex R, Scrutton Nigel S
Manchester Institute of Biotechnology, University of Manchester, Manchester, UK Faculty of Life Sciences, University of Manchester, Manchester, UK.
Department of Biochemistry and Centre for Excellence in Protein Structure and Function, Faculty of Science, Mahidol University, Bangkok, Thailand.
J R Soc Interface. 2015 Feb 6;12(103). doi: 10.1098/rsif.2014.1155.
Environmental exposure to electromagnetic fields is potentially carcinogenic. The radical pair mechanism is considered the most feasible mechanism of interaction between weak magnetic fields encountered in our environment and biochemical systems. Radicals are abundant in biology, both as free radicals and reaction intermediates in enzyme mechanisms. The catalytic cycles of some flavin-dependent enzymes are either known or potentially involve radical pairs. Here, we have investigated the magnetic field sensitivity of a number of flavoenzymes with important cellular roles. We also investigated the magnetic field sensitivity of a model system involving stepwise reduction of a flavin analogue by a nicotinamide analogue-a reaction known to proceed via a radical pair. Under the experimental conditions used, magnetic field sensitivity was not observed in the reaction kinetics from stopped-flow measurements in any of the systems studied. Although widely implicated in radical pair chemistry, we conclude that thermally driven, flavoenzyme-catalysed reactions are unlikely to be influenced by exposure to external magnetic fields.
环境暴露于电磁场可能具有致癌性。自由基对机制被认为是我们环境中遇到的弱磁场与生化系统之间最可行的相互作用机制。自由基在生物学中大量存在，既作为自由基，也作为酶机制中的反应中间体。一些黄素依赖性酶的催化循环要么已知，要么可能涉及自由基对。在这里，我们研究了许多在细胞中起重要作用的黄素酶的磁场敏感性。我们还研究了一个模型系统的磁场敏感性，该系统涉及烟酰胺类似物逐步还原黄素类似物——已知该反应通过自由基对进行。在所使用的实验条件下，在所研究的任何系统中，通过停流测量的反应动力学中均未观察到磁场敏感性。尽管自由基对化学中广泛涉及，但我们得出结论，热驱动的黄素酶催化反应不太可能受到外部磁场暴露的影响。
