The winds of (evolutionary) change: breathing new life into microbiology.
The winds of (evolutionary) change: breathing new life into microbiology.
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DOI：
10.2172/205047
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发表时间：
1996-03
影响因子：
3.2
通讯作者：
G. Olsen;C. Woese;R. Overbeek
中科院分区：
文献类型：
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作者：
G. Olsen;C. Woese;R. Overbeek
到目前为止，超过1500个原核生物的特点是小亚基rRNA测序和分子遗传学有同样深刻的影响，我们了解真核微生物之间的关系。然而，通用的系统发育树很容易显示真核生物和原核生物之间的强烈区别是多么的人为。古菌和细菌之间的分裂现在被认为是主要的系统发育分裂，并且真核生物与古菌从树的同一侧分支。这两个原核结构域似乎都是嗜热起源的，表明生命起源于一个非常温暖的环境。在古生菌中，迄今为止培养的所有泉古菌都是嗜热菌，最深的广古菌分支完全由嗜热菌代表。在细菌中，已知最深的分支又完全由嗜热菌代表，嗜热菌广泛分布在整个领域。该物种包括少数在不寻常的生态位中生长的完全不同的表型。它们都是专性或兼性厌氧菌。所有培养的泉古菌都是嗜热的，有些甚至在高于水的正常沸点的温度下生长最佳。古细菌是硫酸盐还原剂，生长在高温下。极端嗜盐菌只在高盐环境中生长。产甲烷菌局限于各种厌氧生态位，通常是嗜热的。另一方面，细菌是生命光合能力的来源。细菌的五个王国包含光合物种;五个中的每一个都表现出不同类型的（基于叶绿素的）光合作用。
To date, over 1500 prokaryotes have been characterized by small subunit rRNA sequencing and molecular phylogeny has had an equally profound effect on our understanding of relationship among eukaryotic microorganisms. The universal phylogenetic tree readily shows however how artificial the strong distinction between the eukaryote and prokaryotes has become. The split between the Archaea and the Bacteria is now recognized as the primary phylogenetic division and that the Eucarya have branched from the same side of the tree as the Archaea. Both prokaryotic domains would seem to be of thermophilic origin suggesting that life arose in a very warm environment. Among the Archaea, all of the Crenarchaeota cultured to date are thermophiles, and the deepest euryarchaeal branchings are represented exclusively by thermophiles. Among the Bacteria, the deepest known branchings are again represented exclusively by thermophiles, and thermophilia is widely scattered throughout the domain. The Archaea comprise a small number of quite disparate phenotypes that grow in unusual niches. All are obligate or facultative anaerobes. All cultured crenarchaeotes are thermophilic, some even growing optimally above the normal boiling temperature of water. The Archaeoglobales are sulfate reducers growing at high temperatures. The extreme halophiles grow only in highly saline environments. The methanogens are confined to a variety of anaerobic niches, often thermophilic. The Bacteria, on the other hand, are notable as being the source of life`s photosynthetic capacity. Five kingdoms of bacteria contain photosynthetic species; and each of the five manifests a distinct type of (chlorophyll-based) photosynthesis.