4AAO:
reference: MacA is a second cytochrome c peroxidase of Geobacter sulfurreducens., Seidel J, Hoffmann M, Ellis KE, Seidel A, Spatzal T, Gerhardt S, Elliott SJ, Einsle O, Biochemistry. 2012 Apr 3;51(13):2747-56. Epub 2012 Mar 23. PMID: 22417533

This OCA Structure page
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