Life in extreme environments: Approaches to study life-environment co-evolutionary strategies  

作　　者：XIAO Xiang ZHANG Yu 

机构地区：[1]State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University [2]State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University

出　　处：《Science China Earth Sciences》2014年第5期869-877,共9页中国科学（地球科学英文版）

基　　金：supported by National Natural Science Foundation of China (Grant No. 31290232);National High-Tech Program (Grant No. 2012AA092103-2);National Basic Research Program of China (Grant No. 2011CB808800)

摘　　要：The term ＂extreme environments＂ describes the conditions that deviate from what mesophilic cells can tolerate. These condi- tions are ＂extreme＂ in the eye of mankind, but they may be suitable or even essential living conditions for most microorgan- isms. Hypertherrnophilic microorganisms form a branch at the root of the phylogenetic tree, indicating that early life originated from extreme environments similar to that of modern deep-sea hydrothermal vents, which are characterized by high-tempera- ture and oxygen-limiting conditions. During the inevitable cooling and gradual oxidation process on Earth, microorganisms developed similar mechanisms of adaptation. By studying modem extremophiles, we may be able to decode the mysterious history of their genomic evolution and to reconstruct e~,rly life. Because life itself is a process of energy uptake to maintain a dissipative structure that is not in thermodynamic equilibrium, the energy metabolism of microorganisms determines the path- way of evolution, the structure of an ecosystem, and the physiology of cells. ＂Following energy＂ is an essential approach to understand the boundaries of life and to search for life beyond Earth.The term"extreme environments"describes the conditions that deviate from what mesophilic cells can tolerate.These conditions are"extreme"in the eye of mankind,but they may be suitable or even essential living conditions for most microorganisms.Hyperthermophilic microorganisms form a branch at the root of the phylogenetic tree,indicating that early life originated from extreme environments similar to that of modern deep-sea hydrothermal vents,which are characterized by high-temperature and oxygen-limiting conditions.During the inevitable cooling and gradual oxidation process on Earth,microorganisms developed similar mechanisms of adaptation.By studying modern extremophiles,we may be able to decode the mysterious history of their genomic evolution and to reconstruct early life.Because life itself is a process of energy uptake to maintain a dissipative structure that is not in thermodynamic equilibrium,the energy metabolism of microorganisms determines the pathway of evolution,the structure of an ecosystem,and the physiology of cells."Following energy"is an essential approach to understand the boundaries of life and to search for life beyond Earth.

关 键 词：energy EXTREMOPHILE ADAPTATION coevolution 

分 类 号：Q111[生物学—普通生物学]