Local Nanomechanical Motion of the Cell Wall of Saccharomyces cerevisiae

Author: Andrew E. Pelling, Sadaf Sehati, Edith B. Gralla, Joan S. Valentine and James K. Gimzewski
Conference/Journal: Science
Date published: 2004 Aug 20
Other: Volume ID: 305 , Issue ID: 5687 , Pages: 1147-1150 , Special Notes: DOI: 10.1126/science.1097640 , Word Count: 105


We demonstrate that the cell wall of living Saccharomyces cerevisiae (baker's yeast) exhibits local temperature-dependent nanomechanical motion at characteristic frequencies. The periodic motions in the range of 0.8 to 1.6 kHz with amplitudes of ∼3 nm were measured using the cantilever of an atomic force microscope (AFM). Exposure of the cells to a metabolic inhibitor causes the periodic motion to cease. From the strong frequency dependence on temperature, we derive an activation energy of 58 kJ/mol, which is consistent with the cell's metabolism involving molecular motors such as kinesin, dynein, and myosin. The magnitude of the forces observed (∼10 nN) suggests concerted nanomechanical activity is operative in the cell.