4I1B:
reference: Functional implications of interleukin-1 beta based on the three-dimensional structure., Veerapandian B, Gilliland GL, Raag R, Svensson AL, Masui Y, Hirai Y, Poulos TL, Proteins 1992 Jan;12(1):10-23. PMID: 1553379

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