Preliminary crystallographic data of receptors for transport and chemotaxis in Escherichia coli: d-galactose and maltose-binding proteins

We have obtained single crystals of maltose-binding protein ( M r = 40,500) and d-galactose-binding protein ( M r = 32,000), chemoreceptors for active transport and chemotaxis in Escherichia coli. This brings to a total of five the binding proteins that we have thus far crystallized; they include the l-arabinose-binding protein, the leucine, isoleucine, valine-binding protein from Escherichia coli, and a sulfate-binding protein from Salmonella typhimurium. The crystal structure of the l-arabinose-binding protein has been determined at 2.8 Å resolution (Quiocho et al., 1977 a).