1GQ1:
reference: Structure and kinetic properties of Paracoccus pantotrophus cytochrome cd1 nitrite reductase with the d1 heme active site ligand tyrosine 25 replaced by serine., Gordon EH, Sjogren T, Lofqvist M, Richter CD, Allen JW, Higham CW, Hajdu J, Fulop V, Ferguson SJ, J Biol Chem 2003 Apr 4;278(14):11773-81. Epub 2003 Jan 28. PMID: 12556530

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