Diffusion coefficient of CheZ

Range ~10 µm^2/sec
Organism Bacteria Escherichia coli
Reference Segall JE, Ishihara A, Berg HC. Chemotactic signaling in filamentous cells of Escherichia coli. J Bacteriol. 1985 Jan161(1):51-9. p.57 left column bottom paragraphPubMed ID3881399
Method Abstract: "Video techniques were used to record chemotactic responses of filamentous cells of Escherichia coli stimulated iontophoretically with aspartate. Long, nonseptate cells were produced from polyhook strains either by introducing a cell division mutation or by growth in the presence of cephalexin. Markers indicating rotation of flagellar motors were attached with anti-hook antibodies. Aspartate was applied by iontophoretic ejection from a micropipette, and the effects on the direction of rotation of the markers were measured. Motors near the pipette responded, whereas those sufficiently far away did not, even when the pipette was near the cell surface."
Comments P.57 left column bottom paragraph: “An Estimate of the diffusion coefficient of the signal can be made from measurements of signal decay times (3S in cheZ cells, as deduced from measurements of step response kinetics) and decay lengths (about 6 µm In cheZ cells Fig.5B), Which give D~10^-7 cm^2/s.”
Entered by Uri M
ID 112532