1T5X:
reference: A polymorphic pocket at the P10 position contributes to peptide binding specificity in class II MHC proteins., Zavala-Ruiz Z, Strug I, Anderson MW, Gorski J, Stern LJ, Chem Biol 2004 Oct;11(10):1395-402. PMID: 15489166

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