Pautsch A, Schulz G E
Institut für Organische Chemie und Biochemie, Albert-Ludwigs-Universität, Freiburg im Breisgau, Germany.
Nat Struct Biol. 1998 Nov;5(11):1013-7. doi: 10.1038/2983.
The outer membrane protein A of Escherichia coli (OmpA) is an intensely studied example in the field of membrane protein folding. We have determined the structure of the OmpA transmembrane domain consisting of residues 1-171, by X-ray diffraction analysis, to a resolution of 2.5 A. It consists of a regular, extended eight-stranded beta-barrel and appears to be constructed like an inverse micelle with large water-filled cavities, but does not form a pore. Surprisingly, the cavities seem to be highly conserved during evolution. The structure corroborates the concept that all outer membrane proteins consist of beta-barrels. The structure constitutes a beta-barrel membrane anchor that appears to be the outer membrane equivalent of the single-chain alpha-helix anchor of the inner membrane.
大肠杆菌外膜蛋白A（OmpA）是膜蛋白折叠领域中一个被深入研究的例子。我们通过X射线衍射分析确定了由1至171位残基组成的OmpA跨膜结构域的结构，分辨率为2.5埃。它由一个规则的、延伸的八链β桶组成，看起来像是一个带有大的充满水的腔的反胶束，但并不形成孔。令人惊讶的是，这些腔在进化过程中似乎高度保守。该结构证实了所有外膜蛋白都由β桶组成的概念。该结构构成了一个β桶膜锚，它似乎相当于内膜单链α螺旋锚的外膜对应物。
