5G4Z:
reference: Structural basis for ligand recognition by a Cache chemosensory domain that mediates carboxylate sensing in Pseudomonas syringae., Brewster JL, McKellar JL, Finn TJ, Newman J, Peat TS, Gerth ML, Sci Rep. 2016 Oct 13;6:35198. doi: 10.1038/srep35198. PMID: 27734909

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