1K5W:
reference: Three-dimensional structure of the synaptotagmin 1 C2B-domain: synaptotagmin 1 as a phospholipid binding machine., Fernandez I, Arac D, Ubach J, Gerber SH, Shin O, Gao Y, Anderson RG, Sudhof TC, Rizo J, Neuron 2001 Dec 20;32(6):1057-69. PMID: 11754837

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).