6HIH:
reference: One fold, two functions: cytochrome P460 and cytochrome c'-beta from the methanotroph Methylococcus capsulatus (Bath)., Adams HR, Krewson C, Vardanega JE, Fujii S, Moreno T, Chicano, Sambongi Y, Svistunenko D, Paps J, Andrew CR, Hough MA, Chem Sci. 2019 Jan 21;10(10):3031-3041. doi: 10.1039/c8sc05210g. eCollection 2019, Mar 14. PMID: 30996884

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