2GDP:
reference: Activated conformations of the ras-gene-encoded p21 protein. 1. An energy-refined structure for the normal p21 protein complexed with GDP., Dykes DC, Brandt-Rauf P, Luster SM, Chung D, Friedman FK, Pincus MR, J Biomol Struct Dyn. 1992 Jun;9(6):1025-44. PMID: 1637501

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