4KRZ:
reference: Structures of pyruvate kinases display evolutionarily divergent allosteric strategies., Morgan HP, Zhong W, McNae IW, Michels PA, Fothergill-Gilmore LA, Walkinshaw MD, R Soc Open Sci. 2014 Sep 24;1(1):140120. doi: 10.1098/rsos.140120. eCollection, 2014 Sep. PMID: 26064527

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