title: Environments shape the nucleotide composition of genomes.
abstract: To test the impact of environments on genome evolution, we analysed the relative abundance of the nucleotides guanine and cytosine ('GC content') of large numbers of sequences from four distinct environmental samples (ocean surface water, farm soil, an acidophilic mine drainage biofilm and deep-sea whale carcasses). We show that the GC content of complex microbial communities seems to be globally and actively influenced by the environment. The observed nucleotide compositions cannot be easily explained by distinct phylogenetic origins of the species in the environments; the genomic GC content may change faster than was previously thought, and is also reflected in the amino-acid composition of the proteins in these habitats.
authors.affiliation: European Molecular Biology Laboratory, Heidelberg, Germany.
authors.forename: Konrad U
authors.initials: KU
authors.lastname: Foerstner
authors.forename: Christian
authors.initials: C
authors.lastname: von Mering
authors.forename: Sean D
authors.initials: SD
authors.lastname: Hooper
authors.forename: Peer
authors.initials: P
authors.lastname: Bork
mesh_terms: D000596:Amino Acids / Q000737:chemistry; D001105:Archaea / Q000235:genetics; D001419:Bacteria / Q000235:genetics; D001482:Base Composition; D003596:Cytosine; D004777:Environment; D019143:Evolution, Molecular; D016678:Genome; D023281:Genomics; D006147:Guanine; D009711:Nucleotides / Q000737:chemistry*
chemical_list: D000596:Amino Acids; D009711:Nucleotides; D006147:Guanine; D003596:Cytosine