低温细菌与古菌的生物多样性及其冷适应机制  

Biodiversity and cold adaptive mechanisms of psychrophiles

作　　者：辛玉华[1] 周宇光[1] 东秀珠[1] 

机构地区：[1]中国科学院微生物研究所,北京100101

出　　处：《生物多样性》2013年第4期468-480,共13页Biodiversity Science

基　　金：国家自然科学基金重点项目(30830007);国家自然科学基金面上项目(31070001)

摘　　要：低温细菌与古菌广泛分布于地球的低温环境,包括南极、北极及高山地带的冻土、低温土壤和荒漠、冰川、湖泊、海冰,以及深海、冰洞和大气平流层等。栖息在这些低温环境中的细菌与古菌具有丰富的多样性,主要为α,β和γ-Proteobacteria分支、CFB类群分支和革兰氏阳性细菌分支等。由于低温环境中的微生物流动性低,因而是研究微生物地理学理想的生态系统,有助于理解地球微生物的多样性、分布规律乃至形成机制。由于长期生活在冰冻环境中,低温细菌与古菌形成了多种适应低温环境的生理机制,如它们通过细胞膜脂类的组成来调节膜的流动性以维持正常的细胞生理功能;利用相容性溶质、抗冻蛋白、冰核蛋白及抗冰核形成蛋白等实现低温保护作用;产生冷激蛋白、冷适应蛋白和DEAD-boxRNA解旋酶保持低温下RNA的正确折叠、蛋白质翻译等重要的生命活动;另外还产生低温酶,提高能量产生和储存效率等以适应低温环境。随着DNA序列分析技术的飞速发展,各类组学方法也用于揭示微生物全局性的冷适应机制。Cold-adapted bacteria and archaea are widely distributed in cold environments on Earth, such as permafrost, cold soils and deserts, glaciers, lakes, sea ice in the Arctic, Antarctic and high mountains, as well as the deep sea, ice caves and the atmospheric stratosphere etc. Cold-adapted organisms inhabiting these en- vironments exhibit rich diversity. Studies on the biogeography of psychrophiles will enable us to understand their biodiversity, distribution and origins. Due to long-term living in cold regions, cold-adapted bacteria and archeae have developed specific physiological mechanisms of adaptation to cold environments. These mech- anisms include： regulating the fluidity of the cytoplasmic membrane through adjusting the composition of membrane lipids; achieving low-temperature protection through compatibility solute, antifreeze proteins, ice-binding proteins, ice-nucleation proteins and anti-nucleating proteins; production of heat-shock and cold- shock proteins, cold acclimation protein and DEAD-box RNA helicase at low temperatures; production of cold-active enzymes; increasing energy generation and conservation. With the rapid development of se- quencing technology, various omics-based approaches have been used to reveal cold-adaptive mechanisms of Dsvchrot^hiles at the ~enomic level.

关 键 词：低温细菌和古菌 生物多样性 生物地理学 冷适应机制 

分 类 号：Q938[生物学—微生物学]