Role of lipid-bound peptidoglycan precursors in the formation of pores by nisin, epidermin and other lantibiotics
Role of lipid-bound peptidoglycan precursors in the formation of pores by nisin, epidermin and other lantibiotics
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DOI：
10.1046/j.1365-2958.1998.01065.x
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发表时间：
1998-10-01
影响因子：
3.6
通讯作者：
Sahl, HG
中科院分区：
文献类型：
--
作者：
Brötz, H;Josten, M;Sahl, HG
一般认为，A型羊毛硫抗生素主要通过透化细胞质膜来杀死细菌。由于先前的研究表明，乳链菌肽与膜结合的肽聚糖前体脂质I和脂质II相互作用，我们推测这种相互作用可能在羊毛硫抗生素的孔形成过程中起作用。使用薄层层析系统，我们发现，只有乳链菌肽和epidermin，而不是Pep 5，可以形成复合物与[C-14]-脂质II。然后从藤黄微球菌中纯化脂质II，并将其掺入由磷脂酰胆碱和胆固醇（1：1）制成的负载羧基荧光素的脂质体中。当用Pep 5或epilancin K7处理时，补充有0.05或0.1mol%脂质II的脂质体不会释放任何标记物（测试了高达5mol%的肽浓度）。相比之下，少至0.01摩尔%的表皮素和0.1摩尔%的乳酸链球菌素足以诱导快速标记物释放;含磷脂酰甘油的脂质体甚至更敏感。使用莫诺霉素、十一萜醇或十二萜醇磷酸盐掺杂的脂质体的对照证明了羊毛硫抗生素对脂质II的特异性。这些结果与体内模型中的完整细胞相关，M。通过与脂肽雷莫拉宁预孵育来耗尽黄体和模拟葡萄球菌的脂质II，然后测试孔形成。当以低于最小抑菌浓度（MIC）和高达MIC的5-10倍的浓度施用时，乳酸链球菌素和表皮蛋白的孔形成被阻断;在较高浓度的羊毛硫抗生素下，雷莫拉宁的保护作用消失。这些结果表明，在体外和体内，脂质II作为对接分子的乳链菌肽和表皮，但不是Pep 5和epilancin K7，从而促进细胞质膜中的孔的形成。
It is generally assumed that type A lantibiotics primarily kill bacteria by permeabilization of the cytoplasmic membrane, As previous studies had demonstrated that nisin interacts with the membrane-bound peptidoglycan precursors lipid I and lipid II, we presumed that this interaction could play a role in the pore formation process of lantibiotics. Using a thin-layer chromatography system, we found that only nisin and epidermin, but not Pep5, can form a complex with [C-14]-lipid II. Lipid II was then purified from Micrococcus luteus and incorporated into carboxyfluorescein-loaded liposomes made of phosphatidylcholine and cholesterol (1:1). Liposomes supplemented with 0.05 or 0.1 mol% of lipid II did not release any marker when treated with Pep5 or epilancin K7 (peptide concentrations of up to 5 mol% were tested). In contrast, as little as 0.01 mol% of epidermin and 0.1 mol% of nisin were sufficient to induce rapid marker release; phosphatidylglycerol-containing liposomes were even more susceptible. Controls with moenomycin-, undecaprenol- or dodecaprenolphosphate-doped liposomes demonstrated the specificity of the lantibiotics for lipid II. These results were correlated with intact cells in an in vivo model, M. luteus and Staphylococcus simulans were depleted of lipid II by preincubation with the lipopeptide ramoplanin and then tested for pore formation. When applied in concentrations below the minimal inhibitory concentration (MIC) and up to 5-10 times the MIC, the pore formation by nisin and epidermin was blocked; at higher concentrations of the lantibiotics the protective effect of ramoplanin disappeared. These results demonstrate that, in vitro and in vivo, lipid II serves as a docking molecule for nisin and epidermin, but not for Pep5 and epilancin K7, and thereby facilitates the formation of pores in the cytoplasmic membrane.