Skip to Main content Skip to Navigation
Journal articles

A nonhyperthermophilic common ancestor to extant life forms

Abstract : The G+C nucleotide content of ribosomal RNA (rRNA) sequences is strongly correlated with the optimal growth temperature of prokaryotes. This property allows inference of the environmental temperature of the common ancestor to all life forms from knowledge of the G+C content of its rRNA sequences. A model of sequence evolution, assuming varying G+C content among lineages and unequal substitution rates among sites, was devised to estimate ancestral base compositions. This method was applied to rRNA sequences of various species representing the major lineages of life. The inferred G+C content of the common ancestor to extant life forms appears incompatible with survival at high temperature. This finding challenges a widely accepted hypothesis about the origin of life.
Document type :
Journal articles
Complete list of metadata
Contributor : Stéphane Delmotte Connect in order to contact the contributor
Submitted on : Wednesday, October 28, 2009 - 5:29:29 PM
Last modification on : Monday, May 9, 2022 - 11:58:08 AM




N. Galtier, N. Tourasse, Manolo Gouy. A nonhyperthermophilic common ancestor to extant life forms. Science, American Association for the Advancement of Science (AAAS), 1999, 283 (5399), pp.220-221. ⟨10.1126/science.283.5399.220⟩. ⟨hal-00428447⟩



Record views