Competition dynamics in long-term propagations of Schizosaccharomyces pombe strain communities

Experimental evolution studies with microorganisms such as bacteria and yeast have been an increasingly important and powerful tool to draw long-term inferences of how microbes interact. However, while several strains of the same species often exist in natural environments, many ecology and evolution studies in microbes are typically performed with isogenic populations of bacteria or yeast. In the present study, we firstly perform a genotypic and phenotypic characterization of two lab and eight natural strains of the yeast Schizosaccharomyces pombe. We then propagated, in a rich resource environment, yeast communities of 2-, 3-, 4- and 5-strains for hundreds of generations and asked which fitness related phenotypes – maximum growth rate or relative competitive fitness – would better predict the outcome of a focal strain during the propagations. While the strain’s growth rates would wrongly predict long-term co-existence, pairwise competitive fitness with a focal strain qualitatively pre...

以细菌、酵母等微生物为研究对象的实验进化研究，已成为推断微生物间互作长期规律的愈发重要且高效的研究工具。然而，尽管同一物种的多个菌株常共存于自然环境中，但多数微生物生态学与进化研究通常仅采用单一同基因种群的细菌或酵母开展。本研究首先对2株实验室菌株与8株野生（自然）菌株粟酒裂殖酵母（Schizosaccharomyces pombe）进行基因型与表型表征。随后，我们在富营养环境中对由2、3、4、5株菌株组成的酵母群落进行数百代的传代培养，并探究何种与适合度相关的表型——最大生长速率或相对竞争适合度——能够更好地预测传代培养过程中目标菌株的演化结果。尽管菌株的生长速率会错误地预测长期共存情况，而与目标菌株的成对竞争适合度仅能定性地预...