2C61:
reference: Crystal structure of the archaeal A1Ao ATP synthase subunit B from Methanosarcina mazei Go1: Implications of nucleotide-binding differences in the major A1Ao subunits A and B., Schafer IB, Bailer SM, Duser MG, Borsch M, Bernal RA, Stock D, Gruber G, J Mol Biol. 2006 May 5;358(3):725-40. Epub 2006 Mar 10. PMID: 16563431

This OCA Structure page
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