环境胞外胞内DNA的行为归趋及生态功能研究进展

Review of Extracellular and Intracellular DNA Environmental Behavior and Ecological Function

胞外DNA(extracellular DNA,extDNA)和胞内DNA(intracellular DNA,intDNA)广泛存在于陆生和水生生态环境系统中,密切参与环境-微生物和微生物种间的吸附、降解和自然转化等过程,在物质循环和基因信息传递中发挥重要的生态学作用。胞外DNA在环境中不易受核酸酶攻击,相对稳定,可作为历史微生物基因库,与胞内DNA都可反映功能基因丰度及其对应微生物活性;同时,胞外DNA是细胞生物膜中的重要组分,在微生物细胞抵御抗生素、重金属和农药等外来污染物胁迫中发挥了重要作用。本文从ext/intDNA环境行为、extDNA在生物膜中的环境作用、物质信息传递和ext/intDNA生态学功能等角度,综述了环境ext/intDNA的行为归趋及生态功能研究进展,提出了现阶段研究不足,并对未来研究方向进行了展望。本综述可为深入理解环境ext/intDNA的生态功能作用机制提供新的科学认知。

Extracellular DNA(extDNA)and intracellular DNA(intDNA)extensively exist in both terrestrial and aquatic environment systems,and have been found to play a significant role in the nutrient cycling and genetic information transmission between the environment and microorganisms.As inert DNA sequences,extDNA is able to present stably in the environment from the ribosome enzyme lysis,therein act as the historian genetic information archive of the microorganisms.As a consequence,both extDNA and intDNA can shed light on the functional gene variety and the corresponding microbial activity.In addition,extDNA is a ubiquitous composition of cell membrane,which exerts great impact on the resistance of outer stress from environmental pollutants,such as heavy metals,antibiotics,and pesticides,etc.This review focuses on the environmental fate and the ecological functions of the extDNA and intDNA from the perspectives of environmental behavior,genetic information transmission,and resistance to the environmental contaminants,etc.By reviewing the status quo and the future vista of the ext/intDNAs research,this article shed light on the exploring ecological functioning of the ext/intDNAs in the environment.