1QZF:
reference: Phylogenetic classification of protozoa based on the structure of the linker domain in the bifunctional enzyme, dihydrofolate reductase-thymidylate synthase., O'Neil RH, Lilien RH, Donald BR, Stroud RM, Anderson AC, J Biol Chem 2003 Dec 26;278(52):52980-7. Epub 2003 Oct 9. PMID: 14555647

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