1BTZ:
reference: Episelection: novel Ki approximately nanomolar inhibitors of serine proteases selected by binding or chemistry on an enzyme surface., Katz BA, Finer-Moore J, Mortezaei R, Rich DH, Stroud RM, Biochemistry 1995 Jul 4;34(26):8264-80. PMID: 7599119

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