1YGZ:
reference: Structure of inorganic pyrophosphatase from Helicobacter pylori., Wu CA, Lokanath NK, Kim DY, Park HJ, Hwang HY, Kim ST, Suh SW, Kim KK, Acta Crystallogr D Biol Crystallogr 2005 Nov;61(Pt 11):1459-64. Epub 2005, Oct 19. PMID: 16239722

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