3M97:
reference: Structure at 1.5 A resolution of cytochrome c(552) with its flexible linker segment, a membrane-anchored protein from Paracoccus denitrificans., Rajendran C, Ermler U, Ludwig B, Michel H, Acta Crystallogr D Biol Crystallogr. 2010 Jul;66(Pt 7):850-4. Epub 2010, Jun 19. PMID: 20606266

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