The 3.7 Å projection map of the glycerol facilitator GlpF:: a variant of the aquaporin tetramer

被引：37

作者：

Braun, T

Philippsen, A

Wirtz, S

Borgnia, MJ

Agre, P

Kühlbrandt, W

Engel, A

Stahlberg, H

机构：

[1] Univ Basel, Biozentrum, ME Muller Inst Microscopy, CH-4056 Basel, Switzerland

[2] Univ Basel, Biozentrum, Dept Biol Struct, CH-4056 Basel, Switzerland

[3] Johns Hopkins Univ, Sch Med, Dept Biol Chem, Baltimore, MD 21205 USA

[4] Max Planck Inst Biophys, D-60596 Frankfurt, Germany

来源：

EMBO REPORTS | 2000年 / 1卷 / 02期

关键词：

D O I：

10.1093/embo-reports/kvd022

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：

GlpF, the glycerol facilitator protein of Escherichia coli, is an archetypal member of the aquaporin superfamily. To assess its structure, recombinant histidine-tagged protein was overexpressed, solubilized in octylglucoside and purified to homogeneity. Negative stain electron microscopy of solubilized GlpF protein revealed a tetrameric structure of similar to 80 Angstrom side length. Scanning transmission electron microscopy yielded a mass of 170 kDa, corroborating the tetrameric nature of GlpF. Reconstitution of GlpF in the presence of lipids produced highly ordered two-dimensional crystals, which diffracted electrons to 3.6 Angstrom resolution. Cryoelectron microscopy provided a 3.7 Angstrom projection map exhibiting a unit cell comprised of two tetramers. In projection, GlpF is similar to AQP1, the erythrocyte water channel. However, the major density minimum within each monomer is distinctly larger in GlpF than in AQP1.

引用

页码：183 / 189

页数：7

共 35 条

[1] THE MAJOR CELL-ENVELOPE PROTEIN OF MICROCOCCUS-RADIODURANS (R1) - STRUCTURAL AND CHEMICAL CHARACTERIZATION [J].