5A6T:
reference: Kinetic and structural studies reveal a unique binding mode of sulfite to the nickel center in urease., Mazzei L, Cianci M, Benini S, Bertini L, Musiani F, Ciurli S, J Inorg Biochem. 2015 Nov 5;154:42-49. doi: 10.1016/j.jinorgbio.2015.11.003. PMID: 26580226

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