1ML4:
reference: Aspartate transcarbamylase from the hyperthermophilic archaeon Pyrococcus abyssi: thermostability and 1.8A resolution crystal structure of the catalytic subunit complexed with the bisubstrate analogue N-phosphonacetyl-L-aspartate., Van Boxstael S, Cunin R, Khan S, Maes D, J Mol Biol 2003 Feb 7;326(1):203-16. PMID: 12547202

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