This study demonstrates the feasibility and effectiveness of utilizing native soils as a resource for inocula to produce -caproate through the chain elongation (CE) platform, offering new insights into anaerobic soil processes. The results reveal that all five of the tested soil types exhibit CE activity when supplied with high concentrations of ethanol and acetate, highlighting the suitability of soil as an ideal source for -caproate production. Compared with anaerobic sludge and pit mud, the native soil CE system exhibited higher selectivity (60.53%), specificity (82.32%), carbon distribution (60.00%), electron transfer efficiency (165.00%), and conductivity (0.59 ms∙cm). Kinetic analysis further confirmed the superiority of soil in terms of a shorter lag time and higher yield. A microbial community analysis indicated a positive correlation between the relative abundances of , , and and -caproate production. Moreover, metagenomics analysis revealed a higher abundance of functional genes in key microbial species, providing direct insights into the pathways involved in -caproate formation, including CO utilization, ethanol oxidation, fatty acid biosynthesis (FAB), and reverse beta-oxidation (RBO). The numerous functions in FAB and RBO are primarily associated with , , , , and , suggesting that these genera may play roles that are involved or associated with the CE process. Overall, this innovative inoculation strategy offers an efficient microbial source for -caproate production, underscoring the importance of considering CE activity in anaerobic soil microbial ecology and holding potential for significant economic and environmental benefits through soil consortia exploration.

中文翻译：

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使用天然土壤接种物进行链伸长：卓越的正己酸生物合成性能和微生物机制

这项研究证明了利用原生土壤作为接种物资源通过链伸长（CE）平台生产己酸的可行性和有效性，为厌氧土壤过程提供了新的见解。结果表明，当提供高浓度的乙醇和乙酸盐时，所有五种测试的土壤类型均表现出 CE 活性，这凸显了土壤作为己酸生产的理想来源的适用性。与厌氧污泥和坑泥相比，原生土壤CE系统表现出更高的选择性（60.53%）、特异性（82.32%）、碳分布（60.00%）、电子传递效率（165.00%）和电导率（0.59 ms∙cm） 。动力学分析进一步证实了土壤在更短的滞后时间和更高的产量方面的优越性。微生物群落分析表明， 、 、 和 己酸生产的相对丰度之间呈正相关。此外，宏基因组学分析揭示了关键微生物物种中更丰富的功能基因，为了解己酸形成所涉及的途径提供了直接的见解，包括二氧化碳利用、乙醇氧化、脂肪酸生物合成（FAB）和反向β-氧化（RBO） 。 FAB 和 RBO 中的众多功能主要与 、 、 、 和 相关，表明这些属可能发挥与 CE 过程相关或相关的作用。总体而言，这种创新的接种策略为己酸生产提供了有效的微生物来源，强调了在厌氧土壤微生物生态学中考虑CE活动的重要性，并通过土壤联合体探索保持显着经济和环境效益的潜力。