6XNU:
reference: (p)ppGpp and c-di-AMP Homeostasis Is Controlled by CbpB in Listeria monocytogenes., Peterson BN, Young MKM, Luo S, Wang J, Whiteley AT, Woodward JJ, Tong L, Wang JD, Portnoy DA, mBio. 2020 Aug 25;11(4). pii: mBio.01625-20. doi: 10.1128/mBio.01625-20. PMID: 32843560

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