Backbone, side chain and heme resonance assignment of the triheme cytochrome PpcA from Geobacter metallireducens in the oxidized state

3-[(5Z,10Z,14Z,19Z)-18-(2-carboxyethyl)-8,13-bis(ethenyl)-3,7,12,17-tetramethyl-21,23-dihydroporphyrin-2-yl]propanoic acid