Satterlee J D, Erman J E, LaMar G N, Smith K M, Langry K C
Biochim Biophys Acta. 1983 Mar 16;743(2):246-55. doi: 10.1016/0167-4838(83)90221-2.
Assignments of hyperfine shifted proton resonances for the high-spin forms of cytochrome c peroxidase (EC 1.11.1.5) have been made (cytochrome c peroxidase, cytochrome c peroxidase-F) employing the technique of reconstituting the apoprotein with specifically deuterated protohemin IX derivatives. The results show that the heme methyl group pattern differs significantly from similar assignments made for metmyoglobin. In cytochrome c peroxidase the methyl pattern is 5 greater than 1 greater than 8 greater than 3. For cytochrome c peroxidase-F the pattern is 5 greater than 8 greater than 1 greater than 3, but the resonances are not shifted as far downfield and they exhibit a narrower spread. For myoglobin the relative methyl ordering has previously been shown to be 8 greater than 5 greater than 3 greater than 1. Several conclusions have been reached, including confirmation of the essential correspondence between the solution- and crystal-derived data for several heme crevice structural features. The pH dependence of the cytochrome c peroxidase-F methyl resonances is also presented and is shown to differ from native peroxidase. For cytochrome c peroxidase-F smooth, continuous titrations are observed with no evidence of the second conformation which was found for the native enzyme.
利用用特定氘代原血红素IX衍生物重构脱辅基蛋白的技术，对细胞色素c过氧化物酶（EC 1.11.1.5）高自旋形式（细胞色素c过氧化物酶、细胞色素c过氧化物酶-F）的超精细位移质子共振进行了归属。结果表明，血红素甲基模式与对高铁肌红蛋白的类似归属有显著差异。在细胞色素c过氧化物酶中，甲基模式为5大于1大于8大于3。对于细胞色素c过氧化物酶-F，模式为5大于8大于1大于3，但共振没有向低场移动那么远，并且它们的分布较窄。对于肌红蛋白，先前已表明相对甲基排序为8大于5大于3大于1。已经得出了几个结论，包括证实了溶液和晶体衍生数据在几个血红素裂隙结构特征方面的基本对应关系。还给出了细胞色素c过氧化物酶-F甲基共振的pH依赖性，并表明其与天然过氧化物酶不同。对于细胞色素c过氧化物酶-F，观察到平滑、连续的滴定，没有发现天然酶中存在的第二种构象的证据。
