1. Genetic Code and Translation

2. Outline Concepts and Terms related to genetic code Translation Wobble
Degeneracy
isoaccepting
Translation
prokaryote
eukaryotes

3. Amino Acid
Transfer RNA
ribosome

4. Genetic Code Table
1968
Wobble
Degeneracy & mRNA

5. Isoaccepting & tRNAs
Different tRNAs accept same amino acid!

6. We will focus our discussion of translation as a “Nonoverlapping Code”
mRNA sequences

7. Animation of Prokaryotes Translation

8. Steps of Translation 1. Binding of amino acids to tRNA 2. Initiation
3. Elongation
4. Termination
5. Peptide Release
6. Protein modification

9. Step 1 Binding of amino acid to tRNA

10. It takes two steps to “charge” the tRNA
(proofreading activity)
Aminoacyl-tRNA-synthetase
Amino acid+ATP
tRNA is charged

11. Up close view of “charged” tRNA

12. Step 2: Initiation of Translation
Bacterial Initiation
IF3

13. 30S

14. Note 3 ribosomal sites E P A
70S E A

15. Eukaryotic Initiation
Kozak
Eukaryotic Initiation
key differences

16. 3. ELONGATION: look at the “EPA” sites
Peptidyl transferase
(ribozyme of large subunit)

17. Up close view of translation

18. Elongation continues on ribosomes

19. UAA
UAG
UGA
Steps 4 and 5:
Termination and Release

20. 6.
Lipoprotein
Glycoprotein

21. Many antibiotics target prokaryotic translation.

22. Antibiotics and Translation
Bind and block bacterial ribosomes “A” site
Binds to large subunit; blocks peptide formation
Blocks initiation step
Blocks translocation step
Tetracyclines
Chloramphenicol
Streptoymycin
Erythromycin

23. Summary of important steps involved in translation
For your review:
Summary of important steps involved in translation

24. 1. 2.

25. 3.

26. 4.

27. 5.

28. 6. Protein Modifications

29. Eukaryotic translation is very similar except:
More IF’s
Kozak sequence
5’CAP
3’poly-A tail