Mode of action of a bacteriocin from Erwinia carotovora III. properties of phospholipase a of erwinia carotovora and its involvement in phospholipid degradation caused by carotovoricin.
Mode of action of a bacteriocin from Erwinia carotovora III. properties of phospholipase a of erwinia carotovora and its involvement in phospholipid degradation caused by carotovoricin.
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胡萝卜软腐欧文氏菌 III 的细菌素的作用方式。
DOI：
10.2323/jgam.27.239
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发表时间：
1981
影响因子：
1.2
通讯作者：
H. Takahashi
中科院分区：
文献类型：
--
作者：
Y. Itoh;T. Iwata;K. Izaki;H. Takahashi
胡萝卜软腐欧文氏菌（Erwiniacarotovora 645 ArT）外膜磷脂酶A可被胆酸盐、脱氧胆酸盐、Triton X-100和甲醇等去污剂激活。该酶能被乙二胺四乙酸抑制，且酶活性需要Ca ~（2+）。该酶水解磷脂酰乙醇胺和磷脂酰甘油，形成几乎等摩尔量的游离脂肪酸和溶血磷脂。然而，心磷脂对这种酶不敏感。在磷脂酶A活性缺陷的突变株中，由胡萝卜软腐欧文氏菌菌株Er的细菌素胡萝卜软腐菌素Er引起的膜磷脂降解速率在类似条件下下降到亲本菌株的约1/10。在磷脂酶A缺陷突变体中，由胡萝卜素Er引起的裂解也减少了。这些结果表明，胡萝卜素Er在敏感细胞中引起磷脂酶A的活化，从而导致膜磷脂降解和细胞溶解。然而，磷脂酶A缺陷的突变体，仍然保留敏感性胡萝卜素Er的杀伤活性。因此，可以得出结论，磷脂酶A的活化与细菌素的主要杀菌作用无关。
Phospholipase A in the outer membrane of Erwinia carotovora 645ArT was found to be activated by various detergents such as cholate, deoxycholate and Triton X-100, and methanol. The enzyme was inhibited by ethylenediaminetetraacetic acid, and Ca2+ was required for the enzyme activity. The enzyme hydrolyzed phosphatidylethanolamine and phosphatidylglycerol to form nearly equimolar amounts of free fatty acids and lysophospholipids. Cardiolipin, however, was not susceptible to the enzyme. In a mutant strain deficient in the phospholipase A activity, the rate of degradation of membrane phospholipid caused by carotovoricin Er, a bacteriocin from Erwinina carotovora strain Er, declined to about 1/10 of that of the parent strain under similar conditions. Lysis caused by carotovoricin Er also diminished in the phospholipase Adeficient mutant. These results imply that carotovoricin Er provokes an activation of phospholipase A in sensitive cells, and subsequently, degradation of membane phospholipid and cell lysis result. Phospholipase A-deficient mutant, however, still retained sensitivity to killing activity of carotovoricin Er. Hence, it could be concluded that activation of phospholipase A is not related to the primary bactericidal action of the bacteriocin.