3RE6:
reference: Evolved streptavidin mutants reveal key role of loop residue in high-affinity binding., Magalhaes ML, Czekster CM, Guan R, Malashkevich VN, Almo SC, Levy M, Protein Sci. 2011 Jul;20(7):1145-54. doi: 10.1002/pro.642. Epub 2011 May, 12. PMID: 21520321

This OCA Structure page
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