National Institute of Agronomic Research, Regional Center of Errachidia, Errachidia, Morocco.
Department of plant pathology, University of Minnesota, Minneapolis, MN, USA.
Environ Microbiol. 2020 Mar;22(3):976-985. doi: 10.1111/1462-2920.14782. Epub 2019 Sep 1.
Bacteria and fungi are key components of virtually all natural habitats, yet the significance of fungal-bacterial inhibitory interactions for the ecological and evolutionary dynamics of specific bacterial and fungal populations in natural habitats have been overlooked. More specifically, despite the broad consensus that antibiotics play a key role in providing a fitness advantage to competing microbes, the significance of antibiotic production in mediating cross-kingdom coevolutionary interactions has received relatively little attention. Here, we characterize reciprocal inhibition among Streptomyces and Fusarium populations from prairie soil, and explore antibiotic inhibition in relation to niche overlap among sympatric and allopatric populations. We found evidence for local adaptation between Fusarium and Streptomyces populations as indicated by significantly greater inhibition among sympatric than allopatric populations. Additionally, for both taxa, there was a significant positive correlation between the strength of inhibition against the other taxon and the intensity of resource competition from that taxon among sympatric but not allopatric populations. These data suggest that coevolutionary antagonistic interactions between Fusarium and Streptomyces are driven by resource competition, and support the hypothesis that antibiotics act as weapons in mediating bacterial-fungal interactions in soil.
细菌和真菌是几乎所有自然栖息地的关键组成部分，但真菌-细菌抑制相互作用对特定细菌和真菌种群在自然栖息地中的生态和进化动态的意义却被忽视了。更具体地说，尽管人们普遍认为抗生素在为竞争微生物提供适应优势方面发挥着关键作用，但抗生素在介导跨王国协同进化相互作用中的重要性却相对较少受到关注。在这里，我们描述了草原土壤中链霉菌和镰刀菌种群之间的相互抑制作用，并探讨了抗生素抑制作用与同域和异域种群之间生态位重叠的关系。我们发现了镰刀菌和链霉菌种群之间存在局部适应的证据，这表明同域种群之间的抑制作用明显大于异域种群之间的抑制作用。此外，对于这两个分类群，在同域种群中，对另一分类群的抑制强度与来自该分类群的资源竞争强度之间存在显著的正相关关系，但在异域种群中则没有这种关系。这些数据表明，镰刀菌和链霉菌之间的协同进化拮抗相互作用是由资源竞争驱动的，并支持了抗生素在介导土壤中细菌-真菌相互作用方面发挥作用的假设。
