5W1S: X-Ray Crystal Structure Of Escherichia Coli Rna Polymerase A Complex
reference: Allosteric Effector ppGpp Potentiates the Inhibition of Transcript Initiation by DksA., Molodtsov V, Sineva E, Zhang L, Huang X, Cashel M, Ades SE, Murakami KS, Mol Cell. 2018 Mar 1;69(5):828-839.e5. doi: 10.1016/j.molcel.2018.01.035. Epub, 2018 Feb 22. PMID: 29478808

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