REFINED STRUCTURE OF ELONGATION FACTOR-EF-TU FROM ESCHERICHIA-COLI

The crystal structure of trypsin-modified elongation factor Tu from Escherichia coli, in complex with the cofactor guanosine diphosphate has been refined to a crystallographic R-factor of 19.3%, at 2.6 Å resolution. In the model described, the root-mean-square deviation from ideality is 0.019 Å for bond distances and 3.9 ° for angles. The protein consists of three domains: an α β domain (residues 1 to 200), containing the binding site of the GDP cofactor, and consisting of a six-stranded β-pleated sheet, six α-helices, and two all-β domains (residues 209 to 299 and 300 to 393), belonging to the tertiary structural class of antiparallel β-barrels. The GDP-binding domain has a folding that is found in other GDP-binding proteins. Elongation factor Tu interacts with proteins, nucleic acids and nucleotides, making this molecule well suited as a model system for the study of these interactions. © 1992.