- Crystal structure of Escherichia coli inorganic pyrophosphatase complexed with SO4(2-). Ligand-induced molecular asymmetry. Avaeva, S., Kurilova, S., Nazarova, T., Rodina, E., Vorobyeva, N., Sklyankina, V., Grigorjeva, O., Harutyunyan, E., Oganessyan, V., Wilson, K., Dauter, Z., Huber, R., Mather, T. FEBS Lett. (1997)