Three-dimensional structure of the Escherichia coli phosphocarrier protein IIIglc.Worthylake, D., Meadow, N.D., Roseman, S., Liao, D.I., Herzberg, O., Remington, S.J.
(1991) Proc.Natl.Acad.Sci.USA 88: 10382-10386
- PubMed: 1961703
- PubMed Abstract:
- Sugar Transport by the Bacterial Phosphotransferase System. Molecular Cloning and Structural Analysis of the Escherichia Coli Ptsh, Ptsi and Crr Genes
Saffen, D.W.,Presper, K.A.,Doering, T.L.,Roseman, S.
(1987) J.Biol.Chem. 262: 16241
The crystal structure of a proteolytically modified form of the Escherichia coli phosphocarrier and signal transducing protein IIIglc has been determined by multiple isomorphous and molecular replacement. The model has been refined to an R-factor of ...
The crystal structure of a proteolytically modified form of the Escherichia coli phosphocarrier and signal transducing protein IIIglc has been determined by multiple isomorphous and molecular replacement. The model has been refined to an R-factor of 0.166 for data between 6- and 2.1-A resolution with an rms deviation of 0.020 A from ideal bond lengths and 3.2 degrees from ideal bond angles. The molecule is a beta-sheet sandwich, with six antiparallel strands on either side. Several short distorted helices line the periphery of the active site, which is a shallow extremely hydrophobic depression approximately 18 A in diameter near the center of one face. The side chains of the active site histidine residues 75 and 90 face each other at the center of the depression, with the N3 positions exposed to solvent, separated by 3.3 A in an excellent position to form adducts with phosphate. Chloroplatinate forms a divalent adduct with both histidyl side chains, suggesting that the phosphodonor reaction might proceed through a similar transition state. The hydrophobic patch forms the primary crystal contact, suggesting a mode of association of IIIglc with other components of the phosphoenolpyruvate-dependent phosphotransferase system.
Department of Physics, University of Oregon, Eugene 97403.