1PRV:
reference: Structural comparison of the free and DNA-bound forms of the purine repressor DNA-binding domain., Nagadoi A, Morikawa S, Nakamura H, Enari M, Kobayashi K, Yamamoto H, Sampei G, Mizobuchi K, Schumacher MA, Brennan RG, et al., Structure 1995 Nov 15;3(11):1217-24. PMID: 8591032

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