Pinto Javier, Haberkorn Chloé, Franzén Markus, Tack Ayco J M, Stelkens Rike
Department of Zoology, Stockholm University, Stockholm, Sweden.
Department of Biology and Environmental Science, Center for Ecology and Evolution in Microbial Model Systems, Linnaeus University, Kalmar, Sweden.
Environ Microbiol Rep. 2025 Jun;17(3):e70110. doi: 10.1111/1758-2229.70110.
Fermentative yeasts play important roles in both ecological and industrial processes, but their distribution and abundance in natural environments are not well understood. We investigated the diversity of yeasts at the northern range limit of their oak tree hosts (Quercus spp.) in Sweden, and identified climatic and ecological conditions governing their distribution. Yeasts were isolated from bark samples from 28 forests and identified to the species level using DNA metabarcoding. Most communities were dominated by species in the Saccharomycetaceae family, especially by species of Saccharomyces, Kluyveromyces and Pichia. Each genus showed a distinct latitudinal and longitudinal distribution, and both temperature and precipitation metrics predicted significant variation in their abundance. Consistent with this, laboratory assays revealed significant effects of temperature on the growth of strains collected from different longitudes and latitudes. We found that older trees harbour more diverse and more balanced fermentative yeast communities with more evenly distributed species abundances. Communities across trees were more similar when sharing a common dominant species. This work provides a baseline for future studies on the impact of climate change on the fermentative yeast biodiversity of temperate forests in northern latitudes and contributes to a growing collection of wild isolates for potential biotechnological applications.
发酵酵母在生态和工业过程中都发挥着重要作用，但其在自然环境中的分布和丰度尚未得到充分了解。我们调查了瑞典橡树宿主（栎属物种）北部分布界限处酵母的多样性，并确定了控制其分布的气候和生态条件。从28片森林的树皮样本中分离出酵母，并使用DNA宏条形码技术将其鉴定到物种水平。大多数群落以酵母科的物种为主，尤其是酿酒酵母属、克鲁维酵母属和毕赤酵母属的物种。每个属都表现出明显的纬度和经度分布，温度和降水指标都预示着它们丰度的显著变化。与此一致的是，实验室分析表明温度对从不同经度和纬度收集的菌株生长有显著影响。我们发现，老树拥有更多样化、更平衡的发酵酵母群落，物种丰度分布更均匀。当树木共享一个常见的优势物种时，不同树木间的群落更相似。这项工作为未来研究气候变化对北纬温带森林发酵酵母生物多样性的影响提供了基线，并为潜在生物技术应用增加了野生分离株的收集。
