Value 
0.5
sec

Organism 
Budding yeast Saccharomyces cerevisiae 
Reference 
Calculated according to yeast cell diameter and average protein diameter. Please see Measurement Method 
Method 
Taking X, distance to be traveled, as 4.5µm (BNID 100 451) and D in cytoplasm, as 10µm^2/sec (D in cytoplasm is in the range of 515µm^2/sec, GFPBNID 100 193, 40kda dextran, similar weight to protein, BNID 100198). According to equation of diffusion (in 3 dimensions): t diffusion=X^2/(6×D). (4.5µm)^2/60µm^2/sec=0.338sec˜0.5sec. 
Comments 
In cytoplasm there are solutes and D is smaller than in water (100µm^2/sec). D in water can be calculated from the EinsteinStokes eq. D=KBT/6/p/?/R where R=2.5nm, typical protein radius. KB=Boltzmann's constant, ?=viscosity, 0.001 Pa×sec for water. (1.38×10^23Kg×m^2×sec^2×K^1×300K)/ (6×3.14×0.001Kg×m^1×sec^1×2.5×10^9m)=
8.8×10^11m^2/sec=88µm^2sec˜100µm^2/sec 
Entered by 
Uri M 
ID 
104525 