5HPI:
reference: A microbial sensor for organophosphate hydrolysis exploiting an engineered specificity switch in a transcription factor., Jha RK, Kern TL, Kim Y, Tesar C, Jedrzejczak R, Joachimiak A, Strauss CE, Nucleic Acids Res. 2016 Sep 30;44(17):8490-500. doi: 10.1093/nar/gkw687. Epub, 2016 Aug 17. PMID: 27536006

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