GFP diffusion rate in cytoplasm of BL21(DE3) strain

Value 6.1 µm^2/s Range: ±2.4 Table - link µm^2/s
Organism Bacteria Escherichia coli
Reference Konopka MC, Shkel IA, Cayley S, Record MT, Weisshaar JC. Crowding and confinement effects on protein diffusion in vivo. J Bacteriol. 2006 Sep188(17):6115-23. abstract, p.6118 right column bottom paragraph, p.6119 table 1 & p.6122 left column 3rd paragraphPubMed ID16923878
Method FRAP- Fluorescence Recovery After Photobleaching.
Comments Abstract: "For resuspension in isosmotic buffer (osmotic upshift, or Delta, of 0), the mean diffusion coefficient, <D>, in cytoplasm (6.1±2.4µm^2/s) is only 0.07 of the in vitro value (87µm^2/s) the relative dispersion among cells, sigmaD/<D> (standard deviation, sigma(D), relative to the mean), is 0.39. Both <D> and sigmaD/<D> remain remarkably constant over the range of Delta values of 0 to 0.28 osmolal." P.6118 right column bottom paragraph: "[Investigators] obtained diffusion coefficients describing the recovery of 125 cells grown in 0.24 osmolal LB and studied over the range of osmotic upshift values of 0 to 0.7 osmolal. The quantitative results are summarized in Table 1. The 39 cells studied at a Δ of 0 exhibit a broad distribution of diffusion coefficients, as shown by the histograms of D and of log D in Fig. 4. The <D> of 6.1 ± 2.4 μm^2/s (± σD, one standard deviation of single measurements) is 14 times smaller than the diffusion coefficient of GFP in aqueous buffer, where D0 is 87 μm^2/s (ref 34)." P.6122 left column 3rd paragraph: "Finally, [investigators] briefly compared the present results with earlier diffusion studies in both E. coli and eukaryotic cells. The mean diffusion coefficient <D> of 6.1 μm^2/s for GFP in B-strain cells grown in LB at 0.24 osmolal is 14 times slower than a D0 of 87μm^2/s (ref 34), the GFP diffusion coefficient in solution phase." See BNID 100193, 105900
Entered by Uri M
ID 105898