1W9M:
reference: Structural and functional relationships in the hybrid cluster protein family: structure of the anaerobically purified hybrid cluster protein from Desulfovibrio vulgaris at 1.35 A resolution., Aragao D, Mitchell EP, Frazao CF, Carrondo MA, Lindley PF, Acta Crystallogr D Biol Crystallogr. 2008 Jun;64(Pt 6):665-74. Epub 2008, May 14. PMID: 18560155

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