3MG5:
reference: A Distal Point Mutation in the Streptavidin-Biotin Complex Preserves Structure but Diminishes Binding Affinity: Experimental Evidence of Electronic Polarization Effects?, Baugh L, Le Trong I, Cerutti DS, Gulich S, Stayton PS, Stenkamp RE, Lybrand TP, Biochemistry. 2010 May 14. PMID: 20462252

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