1YPC:
reference: Direct observation of better hydration at the N terminus of an alpha-helix with glycine rather than alanine as the N-cap residue., Harpaz Y, Elmasry N, Fersht AR, Henrick K, Proc Natl Acad Sci U S A 1994 Jan 4;91(1):311-5. PMID: 8278384

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