Zgiczyński J M, Stelmaszyńska T
Biochim Biophys Acta. 1979 Apr 12;567(2):309-14. doi: 10.1016/0005-2744(79)90116-5.
The chlorination of glycine by the myeloperoxidase-H2O2-Cl- system at acidic pH values yielded N-monochloroglycine and a mixture of HCN and ClCN. HCN was formed as a product of N-dichloroglycine decomposition and cyanogen chloride formation resulted from simultaneous chlorination of HCN by N-chloroglycine or directly by the myeloperoxidase-H2O2-Cl- system. HCN was readily chlorinated by the myeloperoxidase-H2O2Cl- system yielding cyanogen chloride. This dissociation constants of the myeloperoxidase-CN- complex were estimated as 2.5.10(-6)--1.15.10(-5) M within the pH range of 6.2 to 3.4, respectively. Chloride competed with cyanide for binding at the active site of myeloperoxidase. The lower the pH the more pronounced was the competitive effect of chloride. This accounted for chlorination by myeloperoxidase in the presence of CN-.
在酸性pH值条件下，髓过氧化物酶-H2O2-Cl-系统对甘氨酸进行氯化反应，生成N-一氯甘氨酸以及HCN和ClCN的混合物。HCN是N-二氯甘氨酸分解的产物，而氯化氰的形成是由于HCN被N-氯甘氨酸或直接被髓过氧化物酶-H2O2-Cl-系统同时氯化所致。HCN很容易被髓过氧化物酶-H2O2-Cl-系统氯化生成氯化氰。在pH值为6.2至3.4的范围内，髓过氧化物酶-CN-复合物的解离常数分别估计为2.5×10(-6) - 1.15×10(-5) M。氯离子与氰化物竞争结合髓过氧化物酶的活性位点。pH值越低，氯离子的竞争作用越明显。这就解释了在CN-存在的情况下髓过氧化物酶的氯化作用。
