The quest for a unified view of bacterial land colonization.
Exploring molecular mechanisms underlying bacterial water-to-land transition represents a critical start toward a better understanding of the functioning and stability of the terrestrial ecosystems. Here, we perform comprehensive analyses based on a large variety of bacteria by integrating taxonomic, phylogenetic and metagenomic data, in the quest for a unified view that elucidates genomic, evolutionary and ecological dynamics of the marine progenitors in adapting to nonaquatic environments. We hypothesize that bacterial land colonization is dominated by a single-gene sweep, that is, the emergence of dnaE2 derived from an early duplication event of the primordial dnaE, followed by a series of niche-specific genomic adaptations, including GC content increase, intensive horizontal gene transfer and constant genome expansion. In addition, early bacterial radiation may be stimulated by an explosion of land-borne hosts (for example, plants and animals) after initial land colonization events.
CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China.
Hao
H
Wu
Key Lab of Rubber Biology, Ministry of Agriculture and Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou, China.
Yongjun
Y
Fang
CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China.
Jun
J
Yu
CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China.
Zhang
Z
Zhang
D000222:Adaptation, Physiological; D000818:Animals; D059001:Aquatic Organisms / Q000235:genetics / Q000472:pathogenicity; D001419:Bacteria / Q000145:classification / Q000235:genetics*; D001482:Base Composition; D005075:Biological Evolution; D004258:DNA Polymerase III / Q000235:genetics*; D017753:Ecosystem; D022761:Gene Transfer, Horizontal; D016680:Genome, Bacterial; D054892:Metagenome; D010802:Phylogeny; D010944:Plants / Q000382:microbiology
C074904:DNA polymerase III, alpha subunit; D004258:DNA Polymerase III