| Autor: |
Peter J. Walian, K G Chandy, Seok-Yong Lee, S Ghanshani, Haixin Sui, C.L Wu, Huilin Li, Bing K. Jap |
| Rok vydání: |
1998 |
| Předmět: |
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| Zdroj: |
Journal of Molecular Biology. 282:211-216 |
| ISSN: |
0022-2836 |
| DOI: |
10.1006/jmbi.1998.2016 |
| Popis: |
Potassium channels are integral membrane proteins that play a crucial role in regulating diverse cell functions in both electrically excitable and non-excitable cells. Molecular cloning has revealed a diverse family of genes that encode these proteins, and a variety of experimental strategies have defined functional domains. We have cloned, over-expressed and purified the KcsA potassium channel to homogeneity and reconstituted this channel protein with phospholipids to form two-dimensional crystals. The crystals belong to plane group p4 and have unit cell dimensions of a = b = 48 A. A projection map at 6 A resolution has been obtained by electron crystallography. The map shows that the protein is a homotetramer, having a low-density region on the 4-fold axis that is the site of the ion conduction pathway. Each monomer contains density features that are consistent with the molecular model of a truncated form of KcsA recently determined by X-ray crystallography. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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