MOMP (major outer membrane protein) of Campylobacter jejuni;: a versatile pore-forming protein
MOMP (major outer membrane protein) of Campylobacter jejuni;: a versatile pore-forming protein
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DOI：
10.1016/s0014-5793(00)01244-8
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发表时间：
2000-03-03
期刊：
影响因子：
3.5
通讯作者：
Bolla, JM
中科院分区：
文献类型：
--
作者：
Dé, E;Jullien, M;Bolla, JM
革兰氏阴性菌的绝大多数三聚体孔蛋白不能在不破坏其折叠构象的情况下解离成单体。然而，空肠弯曲杆菌的孔蛋白显示出两种折叠结构，一种是典型的低聚物，另一种是抗洗涤剂变性的单体。我们用光散射实验研究了三聚体向单体的转变，并用红外光谱分析了这两种分子状态的二级结构。研究了三聚体和单体掺入人工脂质双分子层后的离子通道形成特性，在此条件下，三聚体在1 M NaCl中诱导电导值为1200 pS的离子通道。孔具有明显的阳离子选择性和对低电压的敏感性。对分离单体的分析表明，它们具有几乎相同的单通道电导、相同的电压选择性和灵敏度。这些结果表明，折叠单体形式的空肠C. MOMP与天然三聚体具有基本相同的成孔特性。(C) 2000年欧洲生化学会联合会。
The great majority of trimeric porins of Gram-negative bacteria cannot be dissociated into monomers without disrupting their folded conformation. The porin of Campylobacter jejuni, however, displays two folded structures, a classical oligomer and a monomer resistant to detergent denaturation. We probed the transition of trimer to monomer using light scattering experiments and examined the secondary structures of these two molecular states by infra-red spectroscopy. The channel-forming properties of both trimer and monomer were studied after incorporation into artificial lipid bilayers, In these conditions, the trimer induced ion channels with a conductance value of 1200 pS in 1 M NaCl. The pores showed marked cationic selectivity and sensitivity to low voltage. Analysis of the isolated monomer showed nearly the same single-channel conductance and the same selectivity and sensitivity to voltage. These results indicate that the folded monomer form of C. jejuni MOMP displays essentially the same pore-forming properties as the native trimer. (C) 2000 Federation of European Biochemical Societies.