Biochem 501: Part IV.3: DNA Replication

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Biochem 501: Part IV.3: DNA Replication
2013-12-05 19:56:55
Biochem 501 FINAL

Biochem 501 FINAL
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  1. 3 Possible methods for DNA replication
    • Semiconservative
    • Conservative
    • Dispersive
  2. Determining correct model of DNA replication
    • Take Heavy N15 DNA
    • Add to replication conditions contains light N14 material
    • Wait for replication
    • Observe density of outcome:
    • 1 ring=Semi
    • 2 rings=Cons
    • Big blotch=Dispersive
  3. Essential processes of DNA replication:
    Denaturement and Nucleotide polymerization
  4. Steps of DNA replication
    YouTube videos fuckwit
  5. Enzymes that initiate replication
    Helicases (denatures), Primase (makes RNA primers), Topoisomerase II (Relieves strain)
  6. DNA polymerase
    • Needs RNA primer
    • uses dNTPs as substrate
    • Only adds to 3' end (needs 3' OH)
    • Uses Mg2+ to facilitate 3'-OH nucleophilic attack on dNTP phosphate
    • Stabilizes charge
  7. Leading strands are synthesized ______, while lagging strands are synthesized in ______
    Continuously, in sections
  8. Okazaki fragments are connected with:
    DNA ligase
  9. How DNA Ligase functions:
    • DNA ligase picks up AMP
    • AMP transfer activates phosphate
    • DNA ligase catalyzes phosphoryl-transfer reaction to join 3'-OH and 5' phosphate.
  10. DNA polymerase has how many units
    Multiple subunits
  11. DNA Polymerization beta unit is for:
    DNA clamp, used for optimal processivity
  12. Replication fidelity can be disrupted by:
    Base Tautomers
  13. Base tautomers pair with:
    non-standard base partner
  14. How does DNA prevent flaws
    • 3'-5' exonuclease that proofreads
    • Finds flaw, hydrolyizes the bond, pulls polymerase back to fix it