4EKV:
reference: Development of a tetrameric streptavidin mutein with reversible biotin binding capability: engineering a mobile loop as an exit door for biotin., O'Sullivan VJ, Barrette-Ng I, Hommema E, Hermanson GT, Schofield M, Wu SC, Honetschlaeger C, Ng KK, Wong SL, PLoS One. 2012;7(4):e35203. Epub 2012 Apr 19. PMID: 22536357

This OCA Structure page
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