The yield of experimental yeast populations declines during selection.

Department of Biology, Wake Forest University, , Winston-Salem, NC 27106, USA.
Proceedings of the Royal Society B: Biological Sciences (Impact Factor: 5.29). 09/2012; 279(1746):4382-8. DOI: 10.1098/rspb.2012.1659
Source: PubMed

ABSTRACT The trade-off between growth rate and yield can limit population productivity. Here we tested for this life-history trade-off in replicate haploid and diploid populations of Saccharomyces cerevisiae propagated in glucose-limited medium in batch cultures for 5000 generations. The yield of single clones isolated from the haploid lineages, measured as both optical and population density at the end of a growth cycle, declined during selection and was negatively correlated with growth rate. Initially, diploid populations did not pay this cost of adaptation but haploidized after about 1000-3000 generations of selection, and this ploidy transition was associated with a decline in yield caused by reduced cell size. These results demonstrate the experimental evolution of a trade-off between growth rate and yield, caused by antagonistic pleiotropy, during adaptation in haploids and after an adaptive transition from diploidy to haploidy.

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