On the origin of eukaryotes and their endomembranes

Vesteg, Matej, 1982-

On the origin of eukaryotes and their endomembranes / Matej Vesteg, Juraj Krajčovič, Libor Ebringer. -- A novel hypothesis for the origin of eukaryotes is presented. It is assumed that the universal ancestor was bounded by two membranes of heterochiral lipid composition. We propose that the pre-karyote (the hypothetical host entity for alpha-proteobacteria), though sharing a common ancestor with Archaea, was bounded by two membranes. The hypothesis suggests that an a-proteo bacterial symbiont was enclosed in the pre-karyote intermembrane space. In this view, the eukaryotic nuclear membrane and endomembrane system arose from the pre-karyote inner membrane while the eukaryotic plasma membrane arose from the pre-karyote outer membrane. The outlined scenario agrees with the view that engulfment of an alpha-proteobacterial cell by a host entity and its transformation to a mitochondrion was the driving force leading to the appearance of the first eukaryotic cell. The hypothesis seems to be consistent with the pre-cell theory, theory of membrane heredity, and the phagocytosis-late scenario.

In Rivista di biologia. -- Genova : Tilgher-Genova, 2006. -- ISSN 0035-6050. -- ISSN 1825-6538. -- Vol. 99, no. 3 (2006), pp. 499-520