低能量环境中微生物生存策略

Survival strategies of microorganisms in low-energy environments

摘要:

微生物自出现以来，已经在持续变化且能量供应不足的环境中生存和演化了几十亿年。相比于实验室中有机底物充足的培养条件，天然寡营养环境中的微生物在生理状态、基因和蛋白表达等多方面表现出显著不同。在极端且低能量的环境胁迫下，微生物会利用周围环境中的氢气、亚铁离子、矿物、有机残体等多种物质作为能量/电子来源，通过多种方式调节自身基因表达、代谢途径和生理状态来提高能量利用效率，适应寡营养环境，获取维持生命代谢活动的能量并延续种群，驱动物质的转化和元素的循环。因此，深入解析天然环境中微生物的生理状态以及微生物应对低能量供给等环境胁迫时的适应生存机制，对于认识微生物的起源、进化、生长代谢、休眠、维持生命的最低能量极限等都具有重要意义。本文重点介绍了天然低能量环境(即电子供体和碳源缺乏的环境)的形成、演变和分布，以及微生物在变化的低能量环境中的生理状态及其生存策略，该领域的研究有助于推动微生物修复技术的开发、极端环境的生态保护、生物采矿技术的发展，是地质微生物学研究的前沿方向。

Abstract:

Microorganisms have survived and evolved in continuously changing and energy-limited environments for billions of years. Compared with those cultured in laboratories with abundant organic substrates, the microorganisms in natural oligotrophic environments exhibit significant differences in physiological states, gene expression, and protein synthesis. Under extreme and low-energy environmental stress, microorganisms utilize a range of substances such as hydrogen, ferrous ions, minerals, and organic remnants as energy or electron sources. They adjust their gene expression, metabolic pathways, and physiological states through various mechanisms to enhance energy utilization efficiency, adapt to nutrient-scarce conditions, sustain metabolic activities and population survival, and drive material transformation and element cycling. Understanding the physiological states of microorganisms in natural environments and their adaptive mechanisms to low-energy supply is crucial for revealing the microbial origins, evolution, growth, metabolism, dormancy, and the minimum energy requirements for life. This review introduces the formation, evolution, and distribution of natural low-energy environments (i.e., environments deficient in electron donors and carbon sources), as well as the physiological states and survival strategies of microorganisms in these variable low-energy environments. The research in this field advances microbial remediation technology development, extreme environment protection, and bio-mining technology development, representing a frontier in geomicrobiology.