4RWX:
reference: Molecular basis for the recognition of cyclic-di-AMP by PstA, a PII -like signal transduction protein., Choi PH, Sureka K, Woodward JJ, Tong L, Microbiologyopen. 2015 Jun;4(3):361-74. doi: 10.1002/mbo3.243. Epub 2015 Feb 18. PMID: 25693966

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