Enemark John H
Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85711, USA.
Dalton Trans. 2017 Oct 10;46(39):13202-13210. doi: 10.1039/c7dt01731f.
Sulfite-oxidizing enzymes from eukaryotes and prokaryotes have five-coordinate distorted square-pyramidal coordination about the molybdenum atom. The paramagnetic Mo(v) state is easily generated, and over the years four distinct CW EPR spectra have been identified, depending upon enzyme source and the reaction conditions, namely high and low pH (hpH and lpH), phosphate inhibited (P) and sulfite (or blocked). Extensive studies of these paramagnetic forms of sulfite-oxidizing enzymes using variable frequency pulsed electron spin echo (ESE) spectroscopy, isotopic labeling and density functional theory (DFT) calculations have led to the consensus structures that are described here. Errors in some of the previously proposed structures are corrected.
真核生物和原核生物的亚硫酸盐氧化酶在钼原子周围具有五配位扭曲的方锥配位结构。顺磁性的Mo(V)态很容易产生，多年来，根据酶的来源和反应条件，已鉴定出四种不同的连续波电子顺磁共振（CW EPR）光谱，即高pH和低pH（hpH和lpH）、磷酸盐抑制（P）和亚硫酸盐（或封闭）。使用可变频率脉冲电子自旋回波（ESE）光谱、同位素标记和密度泛函理论（DFT）计算对这些亚硫酸盐氧化酶的顺磁性形式进行了广泛研究，得出了此处描述的共有结构。纠正了一些先前提出的结构中的错误。
