2W8X:
reference: An ion-channel modulator from the saliva of the brown ear tick has a highly modified Kunitz/BPTI structure., Paesen GC, Siebold C, Dallas ML, Peers C, Harlos K, Nuttall PA, Nunn MA, Stuart DI, Esnouf RM, J Mol Biol. 2009 Apr 23. PMID: 19394347

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