Persistence length of microtubule

Value 1.4 mm Range: ±0.3 Table - link mm
Organism Generic
Reference van Mameren J, Vermeulen KC, Gittes F, Schmidt CF. Leveraging single protein polymers to measure flexural rigidity. J Phys Chem B. 2009 Mar 26 113(12):3837-44. abstract, p. 3840 right column 4th paragraph & p.3843 table 2PubMed ID19673071
Method "[Researchers] report a new approach to obtain the flexural rigidity by means of well-controlled active experiments using optical tweezers to bend the filaments locally, as schematically depicted in Figure 1. In this way force-extension curves were measured for taxol-stabilized microtubules and rhodamine-phalloidin labeled actin filaments."
Comments "Force-extension curves for microtubules are shown in Figure 5B. Data were recorded for eight different microtubule constructs (four with bead diameter D = 2.2 µm, four with D = 1.5 µm). The same consistency checks were performed with the microtubule constructs as described for actin, assuring the absence of degradation or hysteresis. The curves in Figure 5B are scaled by D2 in order to allow comparison of microtubule constructs with different bead diameters (see eq 3). Figure 6B shows the curves after scaling by the individual EI [flexural rigidity] values, indicating good agreement with the model as in the case of actin. Upon averaging, we obtained EI = (6.1 ± 1.3) × 10^-24 nm^2 or, equivalently, Lp = 1.4 ± 0.3 mm. What is conspicuous when one compares the microtubule results with the actin results is the considerable dispersion of the force-extension curves observed in the case of microtubules which gives rise to a variation of fitted EI values over about a decade in total. Possible reasons for this widely varying behavior will be addressed in the discussion." Value in range is standard error of the mean.
Entered by Uri M
ID 105534