Schwartz C E, Krall J, Norton L, McKay K, Kay D, Lynch R E
J Biol Chem. 1983 May 25;258(10):6277-81.
We assessed the roles of intrabacterial catalase and superoxide dismutase in the resistance of Escherichia coli to killing by neutrophils. E. coli in which the synthesis of superoxide dismutase and catalase were induced by paraquat 10-fold and 5-fold, respectively, did not resist killing by neutrophils. When bacteria were allowed to recover from the toxicity of paraquat for 1 h on ice and for 30 min at 37 degrees C, they still failed to resist killing by neutrophils. Induction of the synthesis of catalase 9-fold by growth in the presence of phenazine methosulfate did not render E. coli resistant to killing by either neutrophils or by H2O2 itself. The lack of protection by intrabacterial catalase from killing by neutrophils could not be attributed to an impermeable bacterial membrane; the evolution of O2 from H2O2 was no less rapid in suspensions of E. coli than in lysates. The failure of intrabacterial catalase or superoxide dismutase to protect bacteria from killing by neutrophils might indicate either that the flux of O-2 and H2O2 in the phagosome is too great for the intrabacterial enzymes to alter or that the site of injury is at the bacterial surface.
我们评估了细菌内过氧化氢酶和超氧化物歧化酶在大肠杆菌抵抗中性粒细胞杀伤中的作用。用百草枯分别诱导超氧化物歧化酶和过氧化氢酶合成增加10倍和5倍的大肠杆菌，对中性粒细胞的杀伤没有抵抗力。当细菌在冰上从百草枯毒性中恢复1小时，然后在37℃恢复30分钟后，它们仍然无法抵抗中性粒细胞的杀伤。在吩嗪硫酸甲酯存在下生长使过氧化氢酶合成增加9倍，这并没有使大肠杆菌对中性粒细胞或过氧化氢本身的杀伤产生抗性。细菌内过氧化氢酶不能保护大肠杆菌免受中性粒细胞杀伤，这不能归因于细菌膜不可渗透；在大肠杆菌悬浮液中，过氧化氢分解产生氧气的速度与在裂解物中一样快。细菌内过氧化氢酶或超氧化物歧化酶不能保护细菌免受中性粒细胞杀伤，这可能表明吞噬小体中O₂和H₂O₂的通量太大，细菌内的酶无法改变，或者损伤部位在细菌表面。
