1LST:
reference: Three-dimensional structures of the periplasmic lysine/arginine/ornithine-binding protein with and without a ligand., Oh BH, Pandit J, Kang CH, Nikaido K, Gokcen S, Ames GF, Kim SH, J Biol Chem 1993 May 25;268(15):11348-55. PMID: 8496186

This OCA Structure page
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