2C4I:
reference: Controlling quaternary structure assembly: subunit interface engineering and crystal structure of dual chain avidin., Hytonen VP, Horha J, Airenne TT, Niskanen EA, Helttunen KJ, Johnson MS, Salminen TA, Kulomaa MS, Nordlund HR, J Mol Biol. 2006 Jun 23;359(5):1352-63. Epub 2006 May 6. PMID: 16787776

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