1G2B:
reference: Atomic resolution structure of a mutant of the spectrin SH3 domain., Berisio R, Viguera A, Serrano L, Wilmanns M, Acta Crystallogr D Biol Crystallogr 2001 Feb;57(Pt 2):337-40. PMID: 11173498

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