5FHD:
reference: Structural and Functional Insights into the Unwinding Mechanism of Bacteroides sp Pif1., Zhou X, Ren W, Bharath SR, Tang X, He Y, Chen C, Liu Z, Li D, Song H, Cell Rep. 2016 Mar 1;14(8):2030-9. doi: 10.1016/j.celrep.2016.02.008. Epub 2016, Feb 18. PMID: 26904952

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