The evolution of the eukaryotic cell

The early evolution of the eukaryotic cell is a problem to be addressed by the study of protozoa. The first eukaryotes were protozoa and it is among the protozoa that representatives of early stages of cellular evolution will be found. Our studies were based on the hypothesis that the first eukaryotes were amitochondriate cells living in anoxic environments. We have isolated previously unknown organisms from these habitats, documented them, and characterised them by ultrastructural and molecular means. Although such cells have impoverished arrays of cytoplasmic organelles, the consensus is that they are primitively amitochondriate and that the hypothesis below has been disproven.

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• Patterson, D.J., Surek, B. and Melkonian, M. (1987). The ultrastructure of Vampyrellidium perforans Surek & Melkonian and its taxonomic position among the naked filose amoebae. Journal of Protozoology, 34: 63-67.
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• Simpson A.G.B. and Patterson, D.J. (1999) The ultrastructure of Carpediemonas membranifera: (Eukaryota), with reference to the excavate hypothesis. European Journal of Protistology, 35: 353-370.
• Simpson, A. G. B. and Patterson, D.J. (2001). On core jakobids and excavate taxa: the ultrastructure of Jakoba incarcerata. J. Euk. Microbial., 48: 480-492.
• Walker, G, Simpson, A.G.B. Edgcomb, V., Sogin, M. L. and Patterson, D.J. 2001. Ultrastructural identities of Mastigamoeba Protozoologica punctachora, Mastigamoeba simplex and Mastigella commutans and assessment of hypotheses of relatedness of the pelobionts (Protista). Europ. J. Protistol. 37, 25-49.
• Weerakoon N.D., Harper J.D.I., Simpson, A.G.B. and Patterson, D.J. (1999). Immunolocalisation of centrin and microtubules in the amitochondriate protist, Chilomastix cuspidata (Retortamonadida). Protoplasma., 210: 75-84.