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 liv...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.展开更多
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)
文摘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.
