3ASY:
reference: A Single Amino Acid Limits the Substrate Specificity of Thermus thermophilus Uridine-Cytidine Kinase to Cytidine., Tomoike F, Nakagawa N, Kuramitsu S, Masui R, Biochemistry. 2011 May 31;50(21):4597-607. Epub 2011 May 3. PMID: 21539325

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