The Met80Ala and Met80Ala/Tyr67Ala variants of S. cerevisiae iso-1 cytochrome c (ycc) and their adducts with cardiolipin immobilized onto a gold electrode coated with a hydrophobic self-assembled monolayer (SAM) of decane-1-thiol were studied through cyclic voltammetry and surface-enhanced resonance Raman spectroscopy (SERRS). The electroactive species - containing a six-coordinate His/His axially ligated heme and a five-coordinate His/- heme stable in the oxidized and reduced state, respectively - and the pseudoperoxidase activity match those found previously for the wt species and are only slightly affected by CL binding. Most importantly, the reduced His/- ligated form of these variants is able to catalytically reduce the nitrite ion, while electrode-immobilized wt ycc and other His/Met heme ligated variants under a variety of conditions are not. Besides the pseudoperoxidase and nitrite reductase functions, which are the most physiologically relevant abilities of these constructs, also axial heme ligation and the equilibria between conformers are strongly affected by the nature - hydrophobic vs. electrostatic - of the non-covalent interactions determining protein immobilization. Also affected are the catalytic activity changes induced by a given mutation as well as those due to partial unfolding due to CL binding. It follows that under the same solution conditions the structural and functional properties of immobilized ycc are surface-specific and therefore cannot be transferred from an immobilized system to another involving different interfacial protein-SAM interactions.

啤酒酵母iso -1细胞色素c的Met80Ala和Met80Ala / Tyr67Ala变体通过循环伏安法和表面增强共振拉曼光谱法（SERRS）研究了ycc及其与心磷脂固定在金电极上的加合物，该金电极上涂覆了癸烷-1-硫醇的疏水性自组装单分子膜（SAM）。电活性物质-分别含有六坐标的His / His轴向连接的血红素和五坐标的His /-血红素稳定于氧化态和还原态-假过氧化物酶的活性与以前对wt物种的活性相符，并且仅略微受CL绑定的影响。最重要的是，这些变体的还原的His /-连接形式能够催化还原亚硝酸根离子，而电极固定的wt ycc和其他His / Met血红素连接的变体在各种条件下却不能。除了伪过氧化物酶和亚硝酸还原酶的功能，这些是这些构建体最生理相关的能力，轴向血红素连接和构象异构体之间的平衡也受到决定蛋白质固定化的非共价相互作用的性质（疏水性与静电性）的强烈影响。同样受到影响的是由给定突变诱导的催化活性变化，以及由于CL结合导致部分展开的催化活性变化。因此，在相同的溶液条件下，固定的ycc的结构和功能特性是表面特异性的，因此无法从固定的系统转移到涉及不同界面蛋白质-SAM相互作用的另一系统。静电-非共价相互作用决定蛋白质的固定化。同样受到影响的是由给定突变诱导的催化活性变化，以及由于CL结合导致部分展开的催化活性变化。因此，在相同的溶液条件下，固定的ycc的结构和功能特性是表面特异性的，因此无法从固定的系统转移到涉及不同界面蛋白质-SAM相互作用的另一系统。静电-非共价相互作用决定蛋白质的固定化。同样受到影响的是由给定突变诱导的催化活性变化，以及由于CL结合导致部分展开的催化活性变化。因此，在相同的溶液条件下，固定的ycc的结构和功能特性是表面特异性的，因此无法从固定的系统转移到涉及不同界面蛋白质-SAM相互作用的另一系统。