MOMP (major outer membrane protein) of Campylobacter jejuni; a versatile pore‐forming protein

FEBS Letters

Bolla, Jean Michel¹  Dé, Emmanuelle²  Labesse, Gilles³  Molle, Gérard²  Pagès, Jean Marie¹  Jullien, Magali³ 

[1] CJF 96-06 INSERM, Faculté de Médecine and Université de la Méditerranée, 27 Bd Jean Moulin, 13385 Marseille Cedex 05, France;UMR 6522, CNRS, IFRMP 23, Faculté des Sciences, 76821 Mont-Saint-Aignan Cedex, France;UMR 9955, CNRS, U 414 INSERM, Faculté de Pharmacie, 34060 Montpellier Cedex, France

关键词: Porin;    Quaternary structure;    Channel-forming property;    Structure/function relationship;   

DOI  :  10.1016/S0014-5793(00)01244-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

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.

【 授权许可】

Unknown