4IU9:
reference: Structure and mechanism of a nitrate transporter., Yan H, Huang W, Yan C, Gong X, Jiang S, Zhao Y, Wang J, Shi Y, Cell Rep. 2013 Mar 28;3(3):716-23. doi: 10.1016/j.celrep.2013.03.007. Epub 2013, Mar 21. PMID: 23523348

This OCA Structure page
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