Aerobiosis increases the genomic guanine plus cytosine content (GC%) in prokaryotes.
The huge variation in the genomic guanine plus cytosine content (GC%) among prokaryotes has been explained by two mutually exclusive hypotheses, namely, selectionist and neutralist. The former proposals have in common the assumption that this feature is a form of adaptation to some ecological or physiological condition. On the other hand, the neutralist interpretation states that the variations are due only to different mutational biases. Since all of the traits that have been proposed by the selectionists either appeared to be limited to certain genera or were invalidated by the availability of more data, they cannot be considered as a selective force influencing the genomic GC% across all prokaryotes. In this report we show that aerobic prokaryotes display a significant increment in genomic GC% in relation to anaerobic ones. This is the first time that a link between a metabolic character and GC% has been found, independently of phylogenetic relationships and with a statistically significant amount of data.
Naya
Hugo
H
Laboratorio de Organización y Evolución del Genoma, Facultad de Ciencias, Iguá 4225, Montevideo 11400, Uruguay.
Romero
Héctor
H
Zavala
Alejandro
A
Alvarez
Beatriz
B
Musto
Héctor
H
D000332:Aerobiosis / Q000235:genetics*; D001105:Archaea / Q000502:physiology; D018407:Bacterial Physiological Phenomena; D001482:Base Composition / Q000235:genetics*; D003596:Cytosine; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D004249:DNA Damage / Q000502:physiology; D045647:DNA Glycosylases; D004260:DNA Repair / Q000502:physiology; D043382:DNA-Formamidopyrimidine Glycosylase; D019143:Evolution, Molecular; D006147:Guanine; D008954:Models, Biological; D009154:Mutation; D009699:N-Glycosyl Hydrolases / Q000502:physiology; D011387:Prokaryotic Cells / Q000502:physiology*; D012641:Selection, Genetic; D013816:Thermodynamics
D006147:Guanine; D003596:Cytosine; D004247:DNA; D045647:DNA Glycosylases; D009699:N-Glycosyl Hydrolases; C061738:mutY adenine glycosylase; D043382:DNA-Formamidopyrimidine Glycosylase