1K6I:
reference: The structure of the negative transcriptional regulator NmrA reveals a structural superfamily which includes the short-chain dehydrogenase/reductases., Stammers DK, Ren J, Leslie K, Nichols CE, Lamb HK, Cocklin S, Dodds A, Hawkins AR, EMBO J 2001 Dec 3;20(23):6619-26. PMID: 11726498

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