Avila-Sakar A J, Creutz C E, Kretsinger R H
Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA.
Biochim Biophys Acta. 1998 Sep 8;1387(1-2):103-16. doi: 10.1016/s0167-4838(98)00111-3.
The crystal structure of a calcium-bound form of bovine annexin VI has been determined with X-ray diffraction data to 2.9 A by molecular replacement. Six Ca2+ ions were found, five in AB loops, one in a DE loop. Two loops (II-AB, which binds calcium, and V-AB, which does not) have conformations that differ significantly from those in calcium-free, human recombinant annexin VI. There are only small differences between the calci- and the apo-annexin VI in the rest of the molecule. Calcium by itself does not promote a major conformational change.
