1QUO:
reference: Structural analysis of a non-contiguous second-site revertant in T4 lysozyme shows that increasing the rigidity of a protein can enhance its stability., Wray JW, Baase WA, Lindstrom JD, Weaver LH, Poteete AR, Matthews BW, J Mol Biol 1999 Oct 8;292(5):1111-20. PMID: 10512706

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