4WK3:
reference: c-di-AMP recognition by Staphylococcus aureus PstA., Muller M, Hopfner KP, Witte G, FEBS Lett. 2015 Jan 2;589(1):45-51. doi: 10.1016/j.febslet.2014.11.022. Epub 2014, Nov 28. PMID: 25435171

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