Reliable cell disruption in yeast

We report the results of an optical assay to determine the degree of cell wall disruption in yeast. The results indicate that cell wall disruption with glass beads yields reproducible results that can be modelled with an integral measure of time to failure that implies a decreasing failure rate. It is shown that a standard protocol results in only 60% disruption, with a relatively large coefficient of variation. The data show that the yield of total RNA harvested is proportional to the degree of cellular disruption, and that there is no loss of RNA quality with >90% disruption. The data also show that cell disruption of a synchronous culture varies with the cell cycle. We speculate that the decreasing failure rate is related to the cell cycle phase-dependent disruptability. (C) 2007 John Wiley & Sons, Ltd.