The Staphylococcus aureus α-toxin channel complex and the effect of Ca2+ ions on its interaction with lipid layers

摘要: Abstract Using the techniques of two-dimensional crystallization on supported lipid bilayers together with computer image processing, two distinct crystal types staphylococcal α-toxin complex are formed depending presence or absence Ca 2+ ions. Without , these hexagonally packed (in A, a = b 89.5 ± 2.5 A; Φ 119.7°) With present, rectangular packing is seen 114.8 1.6 140.2 0.7A; 89.1°). A third, banded type also which interpreted as side-to-side regular tubules. We use tubular crystals for cross-correlation searches top and side-on views from single particle reconstructions, repeating units types. The results lead us to propose model in different result hexamers orientations. In hexagonal lie end-on 6-fold axis projection. On addition reorient tilted respect support, thus giving rise