Arquitetura molecular do motor flagelar bacteriano nas células: 100% design inteligente!

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Molecular Architecture of the Bacterial Flagellar Motor in Cells

Xiaowei Zhao †, Steven J. Norris †‡, and Jun Liu *†

† Department of Pathology and Laboratory Medicine, University of Texas Medical School at Houston, Houston, Texas 77030, United States

‡ Department of Microbiology and Molecular Genetics, University of Texas Medical School at Houston, Houston, Texas 77030, United States

Biochemistry, 2014, 53 (27), pp 4323–4333

DOI: 10.1021/bi500059y

Publication Date (Web): April 3, 2014

Copyright © 2014 American Chemical Society

*Department of Pathology and Laboratory Medicine, University of Texas Medical School at Houston, Houston, TX 77030. E-mail: jun.liu.1@uth.tmc.edu. Phone: (713) 500-5342. Fax: (713) 500-0730.

ACS AuthorChoice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes.



Abstract

The flagellum is one of the most sophisticated self-assembling molecular machines in bacteria. Powered by the proton-motive force, the flagellum rapidly rotates in either a clockwise or counterclockwise direction, which ultimately controls bacterial motility and behavior. Escherichia coli and Salmonella enterica have served as important model systems for extensive genetic, biochemical, and structural analysis of the flagellum, providing unparalleled insights into its structure, function, and gene regulation. Despite these advances, our understanding of flagellar assembly and rotational mechanisms remains incomplete, in part because of the limited structural information available regarding the intact rotor–stator complex and secretion apparatus. Cryo-electron tomography (cryo-ET) has become a valuable imaging technique capable of visualizing the intact flagellar motor in cells at molecular resolution. Because the resolution that can be achieved by cryo-ET with large bacteria (such as E. coli and S. enterica) is limited, analysis of small-diameter bacteria (including Borrelia burgdorferi and Campylobacter jejuni) can provide additional insights into the in situ structure of the flagellar motor and other cellular components. This review is focused on the application of cryo-ET, in combination with genetic and biophysical approaches, to the study of flagellar structures and its potential for improving the understanding of rotor–stator interactions, the rotational switching mechanism, and the secretion and assembly of flagellar components.

FREE PDF GRATIS: Biochemistry

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NOTA DESTE BLOGGER:

E o mascote do Design Inteligente de vento em popa!!! E a Galera de meninos e meninas de Darwin dizem que a complexidade irredutível de sistemas biológicos caiu por terra!

Nada mais falso! Darwin, se vira nego, que sua teoria não explica nem uma bactéria, quanto mais a diversidade e complexidade da vida...