ジャーナル: J Biol Chem / 年: 2006 タイトル: Structural and functional insights into the interaction of echoviruses and decay-accelerating factor. 著者: David M Pettigrew / David T Williams / David Kerrigan / David J Evans / Susan M Lea / David Bhella / 要旨: Many enteroviruses bind to the complement control protein decay-accelerating factor (DAF) to facilitate cell entry. We present here a structure for echovirus (EV) type 12 bound to DAF using cryo- ...Many enteroviruses bind to the complement control protein decay-accelerating factor (DAF) to facilitate cell entry. We present here a structure for echovirus (EV) type 12 bound to DAF using cryo-negative stain transmission electron microscopy and three-dimensional image reconstruction to 16-A resolution, which we interpreted using the atomic structures of EV11 and DAF. DAF binds to a hypervariable region of the capsid close to the 2-fold symmetry axes in an interaction that involves mostly the short consensus repeat 3 domain of DAF and the capsid protein VP2. A bulge in the density for the short consensus repeat 3 domain suggests that a loop at residues 174-180 rearranges to prevent steric collision between closely packed molecules at the 2-fold symmetry axes. Detailed analysis of receptor interactions between a variety of echoviruses and DAF using surface plasmon resonance and comparison of this structure (and our previous work; Bhella, D., Goodfellow, I. G., Roversi, P., Pettigrew, D., Chaudhry, Y., Evans, D. J., and Lea, S. M. (2004) J. Biol. Chem. 279, 8325-8332) with reconstructions published for EV7 bound to DAF support major differences in receptor recognition among these viruses. However, comparison of the electron density for the two virus.receptor complexes (rather than comparisons of the pseudo-atomic models derived from fitting the coordinates into these densities) suggests that the dramatic differences in interaction affinities/specificities may arise from relatively subtle structural differences rather than from large-scale repositioning of the receptor with respect to the virus surface.
タイプ: NEGATIVE 詳細: 5 microlitres of sample was loaded onto a quantifoil grid and then floated on a 20 microlitre droplet of 15% Ammonium Molybdate for 10 seconds, then the grid was blotted for 2 seconds before ...詳細: 5 microlitres of sample was loaded onto a quantifoil grid and then floated on a 20 microlitre droplet of 15% Ammonium Molybdate for 10 seconds, then the grid was blotted for 2 seconds before vitrification in liquid ethane.
グリッド
詳細: 400 mesh R2/2 quantifoils
凍結
凍結剤: ETHANE / 手法: Blot for two seconds, wait for two seconds.
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電子顕微鏡法
顕微鏡
JEOL 1200
温度
平均: 100 K
アライメント法
Legacy - 非点収差: Objective astigmatism corrected at 200,000 times mag