Question 1
Question
Which of the following are caused by hydrolysis?
Answer
-
Nicks
-
Abasic Sites
-
Cross Links
-
Ds Breaks
Question 2
Question
Which of the following are caused by Radical Oxygen Species?
Answer
-
Bulky alkylation damage
-
Abasic sites
-
ds breas
-
ss breaks
-
Nicks
Question 3
Question
What causes Alkylation Damage?
Question 4
Question
Methylation of guanine results in unstable base pairing
Question 5
Question
Over two cycles of replication, a methylated C-G will be replaced with an?
Question 6
Question
What protein catalyses Direct Reversal of Guanine methylation?
Answer
-
Alkyl-Guanine Transferase
-
Adenosyl-Guanine Transferase
-
Adenyl-Guanine Transferase
Question 7
Question
The enzyme involved in direct reversal catalyses the transfer of CH3 to the enzyme, killing it
Question 8
Question
How does the Direct Reversal enzyme 'flip out' the damaged guanine?
Answer
-
A helix-helix motif
-
A helix-turn-helix motif
-
A sheet-turn-sheet motif
Question 9
Question
The enzyme for direct reversal is not specific and so works globally
Question 10
Question
What is the reading head of the Direct Reversal enzyme made of?
Answer
-
Ala & Gly
-
Ser & Val
-
Tyr & Ser
Question 11
Question
The enzyme binds to the major groove using an HTH motif
Question 12
Question
Which happens first in the CH3 transfer?
Answer
-
Lys pushes H onto Tyr
-
Lys pushes CH3 onto Tyr
-
Tyr pushes H onto Lys
Question 13
Question
The new H+ pushes e-....
Answer
-
Onto CH3
-
Onto O bound to CH3
-
Onto Lys bound to CH3
Question 14
Question
The e- added to the O pushes the CH3 onto the Lysine
Question 15
Question
Which of the following recognises the widowed G and fills the gap?
Answer
-
Arg on the head of the reading head
-
Lys on the head of the reading head
-
Val on the head of the reading head
Question 16
Question
UV irradiation of _ causes _?
Answer
-
Consecutive pyrimidines
-
Consecutive purines
-
Opens a 5-6 bond
-
Opens a 3-4 bond
-
Opens a 4-6 bond
Question 17
Question
A phosphobutane photo-dimer is formed
Question 18
Question
Why is UV radiation dangerous?
Question 19
Question
How do 6-4 lesions form?
Answer
-
An O is transfered from on thymine to another
-
An N is transfered from on thymine to another
-
A C is transfered from on thymine to another
Question 20
Question
Damage is recognised by bases
Question 21
Question
How does photolyase work on 6-4 bonds?
Answer
-
Uses light to reverse the reaction
-
Uses UV to reverse the reaction
-
Binds to DNA and excises damaged bases
Question 22
Question
A 'protein wedge' forces DNA apart so it can work
Question 23
Question
An e- from diazaflavin is removed by UV and is passed onto what?
Question 24
Question
The electron will hopefully break the distorted bonds
Question 25
Question
The photolyase process can only work once
Question 26
Question
Which residues bind to the phosphate backbone in photolyase?
Question 27
Question
What does the widowed base pair bind to?