5UK9:
reference: K-Ras Populates Conformational States Differently from Its Isoform H-Ras and Oncogenic Mutant K-RasG12D., Parker JA, Volmar AY, Pavlopoulos S, Mattos C, Structure. 2018 Apr 20. pii: S0969-2126(18)30122-9. doi:, 10.1016/j.str.2018.03.018. PMID: 29706533

This OCA Structure page
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