1UO4:
reference: Structure-based engineering of internal cavities in coiled-coil peptides., Yadav MK, Redman JE, Leman LJ, Alvarez-Gutierrez JM, Zhang Y, Stout CD, Ghadiri MR, Biochemistry. 2005 Jul 19;44(28):9723-32. PMID: 16008357

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