The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark.
Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA.
Nat Commun. 2021 Mar 8;12(1):1498. doi: 10.1038/s41467-021-21844-7.
Sugarcane ethanol fermentation represents a simple microbial community dominated by S. cerevisiae and co-occurring bacteria with a clearly defined functionality. In this study, we dissect the microbial interactions in sugarcane ethanol fermentation by combinatorically reconstituting every possible combination of species, comprising approximately 80% of the biodiversity in terms of relative abundance. Functional landscape analysis shows that higher-order interactions counterbalance the negative effect of pairwise interactions on ethanol yield. In addition, we find that Lactobacillus amylovorus improves the yeast growth rate and ethanol yield by cross-feeding acetaldehyde, as shown by flux balance analysis and laboratory experiments. Our results suggest that Lactobacillus amylovorus could be considered a beneficial bacterium with the potential to improve sugarcane ethanol fermentation yields by almost 3%. These data highlight the biotechnological importance of comprehensively studying microbial communities and could be extended to other microbial systems with relevance to human health and the environment.
甘蔗乙醇发酵代表了一个简单的微生物群落，主要由酿酒酵母和同时存在的细菌组成，它们具有明确的功能。在这项研究中，我们通过组合重建每个可能的物种组合来剖析甘蔗乙醇发酵中的微生物相互作用，这些组合涵盖了相对丰度的约 80%的生物多样性。功能景观分析表明，更高阶的相互作用抵消了成对相互作用对乙醇产量的负面影响。此外，我们发现，通过乙醛的交叉喂养，淀粉乳杆菌可以提高酵母的生长速率和乙醇产量，这通过通量平衡分析和实验室实验得到了证实。我们的结果表明，淀粉乳杆菌可以被认为是一种有益的细菌，有可能将甘蔗乙醇发酵的产量提高近 3%。这些数据突出了全面研究微生物群落的生物技术重要性，并且可以扩展到与人类健康和环境相关的其他微生物系统。
