Close Encounters of the Third Domain: The Emerging Genomic View of Archaeal Diversity and Evolution

Anja Spang,Jimmy H Saw,Joran Martijn,Thijs J G Ettema,Anders E Lind,Lionel Guy

doi:10.1155/2013/202358

Abstract

The Archaea represent the so-called Third Domain of life, which has evolved in parallel with the Bacteria and which is implicated to have played a pivotal role in the emergence of the eukaryotic domain of life. Recent progress in genomic sequencing technologies and cultivation-independent methods has started to unearth a plethora of data of novel, uncultivated archaeal lineages. Here, we review how the availability of such genomic data has revealed several important insights into the diversity, ecological relevance, metabolic capacity, and the origin and evolution of the archaeal domain of life.

Highlights

The description of the three domains of life— Eukarya, Bacteria, and Archaea—by Carl Woese and George Fox [1] represents a milestone in the modern era of microbiology
The Archaea represent the so-called Third Domain of life, which has evolved in parallel with the Bacteria and which is implicated to have played a pivotal role in the emergence of the eukaryotic domain of life
Recent progress in genomic sequencing technologies and cultivation-independent methods has started to unearth a plethora of data of novel, uncultivated archaeal lineages

Summary

Introduction

The description of the three (cellular) domains of life— Eukarya, Bacteria, and Archaea—by Carl Woese and George Fox [1] represents a milestone in the modern era of microbiology. Further investigation of cellular characteristics of archaea has revealed that this domain of life contains eukaryotic-like information-processing machineries [7,8,9,10,11,12,13,14] These findings were later supported by genome sequences and comparative analyses of genes coding for replication, transcription, and translation machineries as well as by protein crystal structures [15,16,17,18,19,20,21]. We give a contemporary overview of how recent developments in archaeal genomic research have contributed to revealing new insights into the diversity, ecological relevance, metabolic capacity, and the origin and evolution of the archaeal domain of life

The Methanogenic Nature of Archaea

Phylogeny of New Archaeal Phyla and Lineages

Archaea and the Origin of Eukaryotes

Genomic Assessment and Taxonomic Classification of Archaeal Diversity