Gouet P, Jouve H M, Williams P A, Andersson I, Andreoletti P, Nussaume L, Hajdu J
Laboratory of Molecular Biophysics, University of Oxford, UK.
Nat Struct Biol. 1996 Nov;3(11):951-6. doi: 10.1038/nsb1196-951.
Various enzymes use semi-stable ferryl intermediates and free radicals during their catalytic cycle, amongst them haem catalases. Structures for two transient intermediates (compounds I and II) of the NADPH-dependent catalase from Proteus mirabilis (PMC) have been determined by time-resolved X-ray crystallography and single crystal microspectrophotometry. The results show the formation and transformation of the ferryl group in the haem, and the unexpected binding of an anion during this reaction at a site distant from the haem.
多种酶在其催化循环过程中会使用半稳定的高铁血红素中间体和自由基，其中包括血红素过氧化氢酶。奇异变形杆菌（PMC）中依赖烟酰胺腺嘌呤二核苷酸磷酸（NADPH）的过氧化氢酶的两种瞬态中间体（化合物I和II）的结构已通过时间分辨X射线晶体学和单晶显微分光光度法确定。结果表明了血红素中高铁血红素基团的形成和转化，以及在此反应过程中一个阴离子在远离血红素的位点发生的意外结合。
