Nakamoto Soma, Kobayashi Ikki, Watanabe Koichi, Kikuta Takeru, Imamura Sousuke, Shimada Tomohiro
School of Agriculture, Meiji University, 1-1-1 Kawasaki-Shi, Tokyo, Kanagawa, 214-8571, Japan.
Space Environment and Energy Laboratories, NTT Corporation, Musashino-Shi, Tokyo, 180-8585, Japan.
Sci Rep. 2025 Feb 4;15(1):4279. doi: 10.1038/s41598-025-85609-8.
Bacteria that typically do not thrive in soil can survive therein for long periods. While much research has been conducted on the external environmental factors affecting the long-term survival of bacteria in soil, their inherent factors are poorly understood. To adapt to environmental changes, bacteria alter their gene expression patterns using transcriptional regulators such as sigma factors. Using Escherichia coli as a model bacterium, we examined the effects of each transcriptional regulator on the long-term survivability of E. coli in soil. The survivability of 294 E. coli strains deficient in transcriptional regulators in soil was measured over 6 weeks. The results showed that ten strains deficient in transcription factors significantly reduced survivability, whereas four deficient strains increased it. The functions common to several of these transcriptional regulators included carbon and nitrogen metabolism, stationary phase adaptation, and osmotic stress adaptation. These transcription factors are often global regulators and conserved among other pathogenic bacterial species. Taken together, we successfully identified a comprehensive set of transcription factors involved in the long-term survival of E. coli in soil. These findings will be useful for understanding the mechanisms underlying the adaptation of microorganisms to soil environments.
通常不在土壤中大量繁殖的细菌能在其中长期存活。虽然针对影响细菌在土壤中长期存活的外部环境因素已开展了大量研究，但对其内在因素却知之甚少。为了适应环境变化，细菌会利用诸如σ因子等转录调节因子来改变其基因表达模式。我们以大肠杆菌作为模式细菌，研究了每种转录调节因子对大肠杆菌在土壤中长期生存能力的影响。对294株缺乏转录调节因子的大肠杆菌菌株在土壤中的生存能力进行了为期6周的测定。结果显示，10株缺乏转录因子的菌株生存能力显著降低，而4株缺乏转录因子的菌株生存能力则有所提高。其中几种转录调节因子共有的功能包括碳氮代谢、稳定期适应和渗透压应激适应。这些转录因子通常是全局调节因子，并且在其他致病细菌物种中保守。综上所述，我们成功鉴定出了一组与大肠杆菌在土壤中长期存活有关的转录因子。这些发现将有助于理解微生物适应土壤环境的潜在机制。
