title: Crystallographic studies of Escherichia coli citrate synthase.
abstract: The citrate synthase from Escherichia coli B has been crystallized in a cubic space group with a unit cell spacing of 220 A. X-ray diffraction, electron microscopy, symmetry considerations, and low resolution projection Patterson syntheses are consistent with a model proposed in which 24 tetrameric molecules of Mr = 188,000 +/- 12,000 occupy the unit cell. The space group is apparently P23, although at low resolution the observed systematic absences in reflections are consistent with the space group P43n, a space group not allowed for asymmetric molecules. Estimates of VM suggest that in the true space group, P23, two tetrameric molecules occupy the asymmetric unit.
mesh_terms: D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002950:Citrate (si)-Synthase; D003461:Crystallography; D004926:Escherichia coli / Q000201:enzymology*; D046911:Macromolecular Substances; D008854:Microscopy, Electron; D008970:Molecular Weight; D007652:Oxo-Acid-Lyases
chemical_list: D046911:Macromolecular Substances; D002950:Citrate (si)-Synthase; D007652:Oxo-Acid-Lyases