Coordinated Rearrangements between Cytoplasmic and Periplasmic Domains of the Membrane Protein Complex ExbB-ExbD of Escherichia coli

被引：15

作者：

Sverzhinsky, Aleksandr ^{[1
]}

Fabre, Lucien ^{[2
]}

Cottreau, Andrew L. ^{[1
]}

Biot-Pelletier, Damien M. P. ^{[1
]}

Khalil, Sofia ^{[1
]}

Bostina, Mihnea ^{[3
]}

Rouiller, Isabelle ^{[2
]}

Coulton, James W. ^{[1
,4
]}

机构：

[1] McGill Univ, Dept Microbiol & Immunol, Montreal, PQ H3A 2B4, Canada

[2] McGill Univ, Dept Anat & Cell Biol, Montreal, PQ H3A 2B4, Canada

[3] McGill Univ, Facil Elect Microscope Res, Montreal, PQ H3A 2B4, Canada

[4] McGill Univ, Microbiome & Dis Tolerance Ctr, Montreal, PQ H3A 2B4, Canada

来源：

STRUCTURE | 2014年 / 22卷 / 05期

基金：

加拿大自然科学与工程研究理事会; 加拿大健康研究院;

关键词：

DEPENDENT ENERGY TRANSDUCTION; OUTER-MEMBRANE; PROTONMOTIVE FORCE; TONB; COMPLEMENTATION; MUTATIONS; TRANSPORT; TOPOLOGY; PATHWAY; FEPA;

D O I：

10.1016/j.str.2014.02.010

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Gram-negative bacteria rely on the ExbB-ExbD-TonB system for the import of essential nutrients. Despite decades of research, the stoichiometry, subunit organization, and mechanism of action of the membrane proteins of the Ton system remain unclear. We copurified ExbB with ExbD as an similar to 240 kDa protein-detergent complex, measured by light scattering and by native gels. Quantitative Coomassie staining revealed a stoichiometry of ExbB(4)-ExbD(2). Negative stain electron microscopy and 2D analysis showed particles of similar to 10 nm diameter in multiple structural states. Nanogold labeling identified the position of the ExbD periplasmic domain. Random conical tilt was used to reconstruct the particles in three structural states followed by sorting of the single particles and refinement of each state. The different states are interpreted by coordinated structural rearrangements between the cytoplasmic domain and the periplasmic domain, concordant with in vivo predictions.

引用

页码：791 / 797

页数：7

共 27 条

[1] CHARACTERIZATION OF THE EXBBD OPERON OF ESCHERICHIA-COLI AND THE ROLE OF EXBB AND EXBD IN TONB FUNCTION AND STABILITY [J].