1EM0:
reference: A DNA-porphyrin minor-groove complex at atomic resolution: the structural consequences of porphyrin ruffling., Bennett M, Krah A, Wien F, Garman E, McKenna R, Sanderson M, Neidle S, Proc Natl Acad Sci U S A 2000 Aug 15;97(17):9476-81. PMID: 10920199

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