4A2M:
reference: A scissor blade-like closing mechanism implicated in transmembrane signaling in a Bacteroides hybrid two-component system., Lowe EC, Basle A, Czjzek M, Firbank SJ, Bolam DN, Proc Natl Acad Sci U S A. 2012 May 8;109(19):7298-303. Epub 2012 Apr 24. PMID: 22532667

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