2IQF:
reference: The structures and electronic configuration of compound I intermediates of Helicobacter pylori and Penicillium vitale catalases determined by X-ray crystallography and QM/MM density functional theory calculations., Alfonso-Prieto M, Borovik A, Carpena X, Murshudov G, Melik-Adamyan W, Fita I, Rovira C, Loewen PC, J Am Chem Soc. 2007 Apr 11;129(14):4193-205. Epub 2007 Mar 15. PMID: 17358056

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