Role of the constriction loop in the gating of outer membrane porin PhoE of Escherichia coli

FEBS Letters

Van Gelder, Patrick¹  Saint, Nathalie²  Tommassen, Jan¹  van Boxtel, Ria¹  Eppens, Elaine F¹ 

[1] Department of Molecular Cell Biology and Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands;Department of Microbiology, Biozentrum, University of Basel, Basel, Switzerland

关键词: PhoE;    Porin;    Outer membrane protein;    Voltage gating;    Constriction loop;    Escherichia coli;   

DOI  :  10.1016/S0014-5793(97)01150-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Porins form voltage-gated channels in the bacterial outer membrane. These proteins are composed of three identical subunits, each forming a 16-stranded β-barrel. In this study, the role in voltage gating of a loop that forms a constriction within the pore was studied. The channel characteristics of mutant PhoE porins, in which the tip of the constriction loop was connected to the barrel wall, were determined. Whereas the properties of several mutant channels were changed, all of these channels could still be closed at high potential, showing that a gross movement of the constriction loop within the channel is not implicated in voltage gating.

【 授权许可】

Unknown