2XVY:
reference: Desulfovibrio vulgaris CbiKP cobaltochelatase: evolution of a haem binding protein orchestrated by the incorporation of two histidine residues., Lobo SA, Videira MA, Pacheco I, Wass MN, Warren MJ, Teixeira M, Matias PM, Romao CV, Saraiva LM, Environ Microbiol. 2016 Aug 3. doi: 10.1111/1462-2920.13479. PMID: 27486032

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