| Autor: |
Krasilnikov OV; Laboratory of Membrane Biophysics, Department of Biophysics and Radiobiology, Federal University of Pernambuco, Av. prof. Moraes Rego, S/N, 50670-901 Recife, PE, Brazil. kras@ufpe.br, Merzlyak PG, Lima VL, Zitzer AO, Valeva A, Yuldasheva LN |
| Jazyk: |
angličtina |
| Zdroj: |
Biochimie [Biochimie] 2007 Mar; Vol. 89 (3), pp. 271-7. Date of Electronic Publication: 2007 Jan 11. |
| DOI: |
10.1016/j.biochi.2006.12.003 |
| Abstrakt: |
Vibrio cholerae cytolysin (VCC) forms oligomeric transmembrane pores in cholesterol-rich membranes. To better understand this process, we used planar bilayer membranes. In symmetric membranes, the rate of the channel formation by VCC has a superlinear dependency on the cholesterol membrane fraction. Thus, more than one cholesterol molecule can facilitate VCC-pore formation. In asymmetric membranes, the rate of pore formation is limited by the leaflet with the lower cholesterol content. Methyl-beta-cyclodextrin, which removes cholesterol from membranes, rapidly inhibits VCC pore formation, even when it is added to the side opposite that of VCC addition. The results suggest that cholesterol in both membrane leaflets aid VCC-pore formation and that either leaflet can function as a kinetic bottleneck with respect to the rate of pore-formation. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
|
Full Text from ScienceDirect