dna replication 3 Flashcards
what will happen if the incorrect nucleotide tried to bind to the dna
there will be outer molecules called steric collutions preventing it from working even if h bonds are made
what is the error rate of pol III
10^-5
how to we decrease pol III error rate
proofreading
what does 3’-5’ exonuclease activity do and how does it work
it removes the last nucleotide added
- the pol III will stall as it recognises the last not was wrong and the end becomes an active site which cleaves the end
what are the 3 activities of pol I
- 5’-3’ polymerase synthesis
- 3’-5’ exonuclease proofreading
- 5’-3’ exonuclease nick translation
if you treat pol I with protease what are the two fragments produced and what are their functions
small n-terminal fragment 5’-3’ exocluease
large c-terminal fragment (Klenow) with polymerase and 3’-5’ exonuclease
how does nick translation work
adds nt to the nicks but also removes all the other nt and replaces them
why can rntps be directly incorporated into DNA strands
the OH on the sugar causes a steric collision
how do we remove rna from the dna within the ozkakai fragments with pol I
it will bind and use 5’-3’ exonuclease
how else can we remove rna from dna
use of rnase to remove all of the DNA other than 1
then pol 1 will remove the final rna and fill the nick
what are the fragments in the leading strand called
pseudo-okazaki fragments
what causes fragments in the leading strand
when pol III places a U nt when it should be T nt, it has to be removed
rna form instead of dna
what causes fragments in the leading strand
when pol III places a U nt when it should be T nt, it has to be removed
rna form instead of dna
what causes fragments in the leading strand
when pol III places a U nt when it should be T nt, it has to be removed
rna form instead of dna
why is u in the dna a problem
if C is deanimated, the binding of U to G will cause a mutation
