BIOL 200 Lecture Notes - Eif6, Tetrahymena, Transfer Rna

• School: McGill University
• Department: Biology (Sci)
• Course: BIOL 200
• Professor: Mathieu Roy

Document Summary

Eukaryotes have 80s ribosomes, each consisting of a small (40s) and large (60s) subunit. 40s subunit has an 18s rna (1900 nucleotides) and 33 proteins. The large subunit is composed of a 5s rna (120 nucleotides), 28s rna (4700 nucleotides), a 5. 8s rna (160 nucleotides) subunits and 46 proteins. During 1977, czernilofsky published research that used affinity labeling to identify trna-binding sites on rat liver ribosomes. L32/33, l36, l21, l23, l28/29 and l13 were implicated as being at or near the peptidyl transferase center. The ribosomes found in chloroplasts and mitochondria of eukaryotes also consist of large and small subunits bound together with proteins into one 70s particle. These organelles are believed to be descendants of bacteria and as such their ribosomes are similar to those of bacteria. The various ribosomes share a core structure, which is quite similar despite the large differences in size.