2V4Y:
reference: Structural and functional characterization of Escherichia coli UMP kinase in complex with its allosteric regulator GTP., Meyer P, Evrin C, Briozzo P, Joly N, Barzu O, Gilles AM, J Biol Chem. 2008 Oct 22. PMID: 18945668

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