NO ADDUCTS OF HEME PROTEINS

X射线吸收光谱分析将用于研究 与生物相关，不与血红素蛋白结合。最初，这样的 血红素蛋白的加合物是许多振动、UV/VIS的目标 和EPR波谱研究，以模拟氧的结合 以获取更多有关血红素口袋的信息。然而， 自那以后，研究无加成物本身就变得重要起来。 发现与氯化血红素没有结合有许多生理作用。 本项目涉及无结合的XAS研究 硝基苯酚，吲哚-2，3-双加氧酶，豆红蛋白a突变体和 马心细胞色素c.边缘数据将用于确定 ‘Fe(III)-NO’加合物中铁的氧化状态 根据拉曼光谱最好地描述为Fe(II)-NO+络合物， 而XAFS将用于提供Fe-L键的精确测定 Fe(III)和Fe(II)中的长度和Fe-N-O角 蛋白质的加合物。变温工作也将 在模型复合体上执行，以检查角度如何随 温度。这些研究将被用来确定更多信息 关于电子和分子结构中涉及的 生理上相关的无约束力。

X-ray absorption spectroscopy will be used to study biologically-relevant NO binding to heme proteins. Initially, such adducts of heme proteins were the subject of many vibrational, UV/Vis and EPR spectroscopy studies in order to model the binding of dioxygen to heme proteins and find out more about the heme pocket. However, the study of NO adducts has become important in its own right since the discovery that NO binding to hemes has many physiological roles. The present project involves XAS studies of NO binding to nitrophorins, indoleamine-2,3-dioxygenase, leghemoglobin a mutants and horse heart cytochrome c. Edge data will be used to determine the oxidation state of Fe in the 'Fe(III)-NO' adducts that are thought to be best described as Fe(II)-NO+ complexes from Raman spectroscopy, while XAFS will be used to provide precise determinations of Fe-L bond lengths and of the Fe-N-O angle in both the 'Fe(III)' and Fe(II) adducts of the proteins. Variable temperature work will also be performed on model complexes to examine how the angle changes with temperature. These studies will be used to determine more information about the electronic and molecular structures involved in the physiologically-relevant NO binding.