4TQL:
reference: High thermodynamic stability of parametrically designed helical bundles., Huang PS, Oberdorfer G, Xu C, Pei XY, Nannenga BL, Rogers JM, DiMaio F, Gonen T, Luisi B, Baker D, Science. 2014 Oct 24;346(6208):481-5. doi: 10.1126/science.1257481. PMID: 25342806

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