RT Journal Article
SR Electronic
T1 The mechanical properties of *Saccharomyces cerevisiae*
JF Proceedings of the National Academy of Sciences
JO Proc Natl Acad Sci USA
FD National Academy of Sciences
SP 9871
OP 9874
DO 10.1073/pnas.97.18.9871
VO 97
IS 18
A1 Smith, Alexander E.
A1 Zhang, Zhibing
A1 Thomas, Colin R.
A1 Moxham, Kennith E.
A1 Middelberg, Anton P. J.
YR 2000
UL http://www.pnas.org/content/97/18/9871.abstract
AB Cell-wall mechanical properties play an integral part in the growth and form of Saccharomyces cerevisiae. In contrast to the tremendous knowledge on the genetics of S. cerevisiae, almost nothing is known about its mechanical properties. We have developed a micromanipulation technique to measure the force required to burst single cells and have recently established a mathematical model to extract the mechanical properties of the cell wall from such data. Here we determine the average surface modulus of the S. cerevisiae cell wall to be 11.1 ± 0.6 N/m and 12.9 ± 0.7 N/m in exponential and stationary phases, respectively, giving corresponding Young's moduli of 112 ± 6 MPa and 107 ± 6 MPa. This result demonstrates that yeast cell populations strengthen as they enter stationary phase by increasing wall thickness and hence the surface modulus, without altering the average elastic properties of the cell-wall material. We also determined the average breaking strain of the cell wall to be 82% ± 3% in exponential phase and 80% ± 3% in stationary phase. This finding provides a failure criterion that can be used to predict when applied stresses (e.g., because of fluid flow) will lead to wall rupture. This work analyzes yeast compression experiments in different growth phases by using engineering methodology.