Protein Description
[color=#333333]Annexins are a family of calcium- and phospholipid-binding proteins implicated in a number of biological processes including membrane fusion and ion channel formation. The crystal structure of the annexin XII hexamer, refined at 2.8 A resolution, forms a concave disk with 3-2 symmetry, about 100 A in diameter and 70 A thick with a central hydrophilic pore. Six intermolecular Ca2+ ions are involved in hexamer formation. An additional 18 Ca2+ ions are located on the perimeter of the disk, accessible only from the side of the hexameric disk. On the basis of the hexamer structure we propose here a new mode of protein-phospholipid bilayer interaction that is distinct from the hydrophobic insertion of typical membrane proteins. This speculative model postulates the Ca(2+)-dependent insertion of the hydrophilic annexin XII hexamer into phospholipid bilayers with local reorientation of the bilayer phospholipids.[/color]
https://www.rcsb.org/pdb/explore.do?structureId=1AEI
Model Description
Annexin B12 Trimer created from PDB ID: 1AEI 3D printed in full-color sandstone. (Chain A: Yellow, Chain B: Cyan, Chain C: Green, Residues of AB repeats: Red, DE repeats: Magenta)