Structural basis topological specificity function of MinE

Correct positioning of the division septum in Escherichia coli depends on t he coordinated action of the MinC, MinD and MinE proteins. Topological spec ificity is conferred on the MinCD division inhibitor by MinE, which counter s MinCD activity only in the vicinity of the preferred midcell division sit e. Here we report the structure of the homodimeric topological specificity domain of Escherichia coli MinE and show that it forms a novel ap sandwich, Structure-directed mutagenesis of conserved surface residues has enabled u s to identify a spatially restricted site on the surface of the protein tha t is critical for the topological specificity function of MinE.