5A2N:
reference: Molecular basis of nitrate uptake by the plant nitrate transporter NRT1.1., Parker JL, Newstead S, Nature. 2014 Mar 6;507(7490):68-72. doi: 10.1038/nature13116. Epub 2014 Feb 26. PMID: 24572366

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