Puustinen A
Department of Medical Chemistry, University of Helsinki, Finland.
Acta Physiol Scand Suppl. 1992;607:265-8.
The b-type haem groups of cytochrome o have generally been thought to be protohaems. However, we have recently shown that they are of a novel kind, for which we propose the name haem O. On the basis of its pyridine haemochrome spectrum, chromatographic behaviour and molecular mass of 839 Da, we suggest that haem O is a haem A-like molecule with the formyl group in position 8 of the latter replaced by methyl, but with retention of the 17-carbon hydroxyethyl-farnesyl side chain in position 2, characteristic of haem A. This structure has now been unambiguously verified by resonance Raman, 1H-NMR, and infrared spectroscopy, as well as by mass spectroscopy of molecular fragments, in collaboration with C. K. Chang, G. T. Babcock and their co-workers at Michigan State University. Properties of haem O are compared with haem A and protohaem, and possible contributions of haem O structure to the cytochrome o oxidase function are discussed.
细胞色素o的b型血红素基团通常被认为是原血红素。然而，我们最近发现它们是一种新型的血红素，我们将其命名为血红素O。基于其吡啶血红素光谱、色谱行为和839 Da的分子量，我们认为血红素O是一种类似血红素A的分子，其中后者8位的甲酰基被甲基取代，但保留了2位17碳羟乙基法尼基侧链，这是血红素A的特征。现在，通过共振拉曼光谱、1H-NMR、红外光谱以及分子碎片质谱，与密歇根州立大学的C.K.张、G.T.巴布科克及其同事合作，这一结构已得到明确验证。将血红素O的性质与血红素A和原血红素进行了比较，并讨论了血红素O结构对细胞色素o氧化酶功能的可能贡献。
