1D6N:
reference: Ternary complex structure of human HGPRTase, PRPP, Mg2+, and the inhibitor HPP reveals the involvement of the flexible loop in substrate binding., Balendiran GK, Molina JA, Xu Y, Torres-Martinez J, Stevens R, Focia PJ, Eakin AE, Sacchettini JC, Craig SP 3rd, Protein Sci 1999 May;8(5):1023-31. PMID: 10338013

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