1. LEHNINGER PRINCIPLES OF BIOCHEMISTRY Sixth Edition David L. Nelson and Michael M. Cox © 2013 W. H. Freeman and Company CHAPTER 8 Nucleotides and Nucleic Acids

2. Cellular Processes DNA RNA (mRNA) Proteins LipidsCarbohydrates replication transcription translation

3. Structure of Nucleotides

8. Phosphodiester linkages in the covalent backbone of DNA and RNA

9. Hydrolysis of RNA under alkaline conditions

10. Absorption spectra of the common nucleotides

11. Hydrogen bonding between complementary DNA strands

12. Watson – Crick model for the structure of DNA

13. Certain DNA sequences adopt unusual structures

14. A single DNA strand with self complementary sequences can form a hairpin structure

15. Double stranded DNA with self complementary sequences can form a cruciform structure

16. Hoogsteen base pairs form in triplex DNA A single strand of DNA, typically a string of pyrimidines, hydrogen bonds in the major groove of a double-stranded DNA Red strand is in the major groove

17. Four DNA strands containing a high proportion of guanosines can form a G tetraplex

18. Cellular Processes DNA RNA (mRNA) Proteins LipidsCarbohydrates replication transcription translation

19. mRNA molecules can be monocistronic (containing one gene) or polycistronic (containing multiple genes) In eukaryotes most mRNAs are monocistronic In prokaryotes many mRNAs are polycistronic

20. Secondary structure of RNA

21. M1 RNA component of the enzyme Rnase P of E. coli

22. Reversible denaturation and annealing (renaturation) of DNA

23. When DNA is denatured the melting point is when half of the DNA is present as separated single strands The greater the G-C content, the higher the melting point (t m )

24. Electron micrograph showing partially denatured DNA Red arrows indicate regions of high A-T content, which denature first

25. Spontaneous loss of an exocyclic amino group is deamination Around 100 times per day in a cell

26. Nitrous acid (HNO 2 ) promotes deamination reactions

27. Hydrolysis of the bond between the base and the ribose creates an apurininc site in DNA Around 10,000 times per day in a cell

28. Pyrimidine dimers are induced by exposure to UV light

29. Nucleotides found in biomolecules