Protein Synthesis by Amoebal Ribosomes

ALTHOUGH some of the first observations localizing the site of protein biosynthesis to microsomes were made with Tetrahymena1, interest in protozoa has generally been overshadowed by that shown for bacteria, yeast or rat liver, as appropriate cells in which to study the mechanisms of protein synthesis. None the less, the possibilities of variation in the organization of polysomes or in genetic code assignments make these organisms of prime interest. The availability of axenic cultures of Entamoeba histolytica2, an important pathogen for man (amoebic dysentery and amoebic liver abscess), prompted us to study the polyribosomes of this organism. At present, only the trophozoite can be cultivated axenically.