Growth characteristics of FY834 under high ethanol concentrations.

<p>(A) Growth characteristics of FY834 in repetitive cultivations at high ethanol concentrations. FY834 was inoculated into medium containing 2.5, 5, 6.5, 8, 9 or 10% ethanol, respectively, and then the growth of each culture was monitored, measuring OD₆₆₀. In each culture, the culture broth was transferred to fresh medium containing the same ethanol concentration and then the growth was observed. The timing of the transfer to fresh medium is shown by the dotted lines. (B) Growth characteristics during subjection of FY834 to stepwise increase in ethanol concentration with repetitive cultivations. The method used for subjecting the yeast cells to a stepwise increase in ethanol concentration is described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0002623#s3" target="_blank">Materials and methods</a>. The timing of the transfer of culture to fresh medium is shown by the dotted lines. In the experiment shown in this figure, we obtained an ethanol-adapted strain series A2.