Drozdz R, Naskalski J W
Diagnostic Department, Chair of Clinical Biochemistry, University School of Medicine, Kraków, Poland.
Folia Histochem Cytobiol. 1993;31(2):71-5.
Changes in biological properties of serum albumin, egg white lysozyme, human serum alpha-1 antiproteinase and human leukocyte ribonuclease in effect of interaction with the enzyme system composed of myeloperoxidase from human neutrophilic polymorphonuclear leukocytes, Cl- and H2O2 were investigated. All the studied proteins lost their biological functions and were denaturated, but the amounts of hydrogen peroxide necessary to produce these effects differed remarkably for each individual protein. The alpha-1 antiproteinase ability of binding to trypsin was abolished upon employing 1.2 mols of H2O2 per mol of alpha-1 antiproteinase. The lysozyme enzymatic activity was abolished when 1.4 mols of H2O2 per mol of lysozyme were employed. Albumin decreased its binding to specific antialbumin antibodies and entirely lost the binding properties when 2 mols and about 10 mols of H2O2 per mol of albumin were employed, respectively. On the other hand 18 mols of H2O2 per mol of human leukocyte ribonuclease were necessary to inactivate this enzyme. All the mentioned proteins were protected from losing their biological functions by excess of specific amino acids with affinity to hypochlorite: Alpha-1 antiproteinase by excess of N-acetylmethionine, lysozyme by N-acetylmethionine and N-acetyl glycyltryptophane, albumin by N-acetyl derivatives of methionine, cysteine, tryptophane and lysine, whereas ribonuclease was protected from denaturation by all above mentioned amino acid derivatives. None of the studied proteins was protected from denaturation by N-acetyl tyrosine, or phenylalanine.
研究了血清白蛋白、蛋清溶菌酶、人血清α-1抗蛋白酶和人白细胞核糖核酸酶与由人嗜中性多形核白细胞髓过氧化物酶、Cl⁻和H₂O₂组成的酶系统相互作用时生物学性质的变化。所有研究的蛋白质都失去了它们的生物学功能并发生了变性，但产生这些效应所需的过氧化氢量因每种蛋白质而异。每摩尔α-1抗蛋白酶使用1.2摩尔H₂O₂时，其与胰蛋白酶结合的能力被消除。每摩尔溶菌酶使用1.4摩尔H₂O₂时，溶菌酶的酶活性被消除。当每摩尔白蛋白分别使用2摩尔和约10摩尔H₂O₂时，白蛋白与特异性抗白蛋白抗体的结合减少并完全失去结合特性。另一方面，每摩尔人白细胞核糖核酸酶需要18摩尔H₂O₂才能使该酶失活。所有上述蛋白质都通过与次氯酸盐具有亲和力的过量特定氨基酸而免受生物学功能丧失的影响：α-1抗蛋白酶通过过量的N-乙酰甲硫氨酸，溶菌酶通过N-乙酰甲硫氨酸和N-乙酰甘氨酰色氨酸，白蛋白通过甲硫氨酸、半胱氨酸、色氨酸和赖氨酸的N-乙酰衍生物，而核糖核酸酶则通过上述所有氨基酸衍生物免受变性。所研究的蛋白质均未因N-乙酰酪氨酸或苯丙氨酸而免受变性影响。
