Resumen de The universal ancestor: an unfinished reconstruction

Arturo Becerra, Luis Delaye Arredondo

• The cenancestor is defined as the last common ancestor of every currently living being. Its nature has been inferred from the identification of homologous genes between archaea, bacteria, and eukaryotic lineages. These inferences indicate that the cenancestor had a relatively modern protein translation system, similar in complexity to that of a current cell. However, the key enzymes for the replication of genetic material and for cell membrane biosynthesis are not homologous in bacteria, archaea, and eukaryotes. Here, we briefly review the history of the concept of the last universal common ancestor and the different hypotheses proposed for its biology.