4CCP:
reference: X-ray structures of recombinant yeast cytochrome c peroxidase and three heme-cleft mutants prepared by site-directed mutagenesis., Wang JM, Mauro M, Edwards SL, Oatley SJ, Fishel LA, Ashford VA, Xuong NH, Kraut J, Biochemistry 1990 Aug 7;29(31):7160-73. PMID: 2169873

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