Myeloperoxidase-Hydrogen Peroxide-Chloride Antimicrobial System: Effect of Exogenous Amines on Antibacterial Action Against Escherichia coli
Myeloperoxidase-Hydrogen Peroxide-Chloride Antimicrobial System: Effect of Exogenous Amines on Antibacterial Action Against Escherichia coli
复制标题
髓过氧化物酶-过氧化氢-氯化物抗菌系统：外源胺对大肠杆菌抗菌作用的影响
作者：
E. Thomas
外源氨离子(NH4+)和胺类化合物对髓过氧化物酶-过氧化氢-氯化物体系的抗菌活性有较大影响。在NH4+和某些胍基化合物的存在下，杀伤率增加，而在α-氨基酸、多赖氨酸、牛磺酸或三(羟甲基)氨基甲烷的存在下，杀伤率降低。髓过氧化物酶催化氯化物氧化成次氯酸，次氯酸与细菌胺或酰胺组分或两者或与外源化合物反应生成氯胺或氯胺衍生物或两者。这些氮氯衍生物可以氧化细菌成分。杀灭与细菌成分的氧化有关。在增加杀灭率的化合物存在时，细菌巯基的氧化速率增加，而在其他化合物存在时则降低。HOCl与NH4+反应生成一氯胺(NH_2Cl)，可从有机溶剂中提取。细菌成分或聚赖氨酸、牛磺酸或三(羟甲基)氨基甲烷的N-Cl衍生物不能被提取。NH4+的杀灭作用归因于NH_2Cl穿透疏水细胞膜从而氧化细胞内组分的能力。多聚赖氨酸、牛磺酸和三(羟甲基)氨基甲烷形成不能穿透细胞膜的高相对分子质量、带电荷或极性的N-Cl衍生物。这些结果表明，白细胞胺成分在体内髓过氧化物酶催化的抗菌活性中起着重要作用。
Exogenous ammonium ions (NH4+) and amine compounds had a profound influence on the antibacterial activity of the myeloperoxidase-hydrogen peroxide-chloride system against Escherichia coli. The rate of killing increased in the presence of NH4+ and certain guanidino compounds and decreased in the presence of α-amino acids, polylysine, taurine, or tris (hydroxymethyl) aminomethane. Myeloperoxidase catalyzed the oxidation of chloride to hypochlorous acid, which reacted either with bacterial amine or amide components or both or with the exogenous compounds to yield chloramine or chloramide derivatives or both. These nitrogen-chlorine derivatives could oxidize bacterial components. Killing was correlated with oxidation of bacterial components. The rate of oxidation of bacterial sulfhydryls increased in the presence of the compounds that increased the rate of killing and decreased in the presence of the other compounds. The reaction of HOCl with NH4+ yielded monochloramine (NH2Cl), which could be extracted into organic solvents. The N-Cl derivatives of bacterial components or of polylysine, taurine, or tris(hydroxymethyl)aminomethane could not be extracted. The effect of NH4+ on killing is attributed to the ability of NH2Cl to penetrate the hydrophobic cell membrane and thus to oxidize intracellular components. Polylysine, taurine, and tris(hydroxymethyl)aminomethane formed high-molecular-weight, charged, or polar N-Cl derivatives that would be unable to penetrate the cell membrane. These results suggest an important role for leukocyte amine components in myeloperoxidase-catalyzed antimicrobial activity in vivo.