Term
| Holoenzyme (active DNA pol III) |
|
Definition
Core-elongates polynucleotide chain & proofreads
Sliding DNA clamp-leads strands through synthesis
T (tau subunit)-dimerizes core complex
Quick stop: very close to the beginning of the replication fork and chain elongation cannot occur when mutation activates. |
|
|
Term
| DNA gyrase (topoisomerase II) |
|
Definition
Single or double stranded cuts+undoes twists/knots formed during super coiling before the DNA is synthesized (DNA strands are resealed at the end)
Quick stop; torsional strain will quickly build and block the helicase from unwinding the DNA |
|
|
Term
|
Definition
Short segment of RNA that the holoenzyme adds deoxyribonucleotides to & initiates DNA synthesis
(Note: synthesis is in the 5' to 3' direction which is why synthesis segments are formed on the lagging stand BUT primase doesn't need to attach to a free OH group to function)
Quick stop*: new fragments cannot be formed and the fork stalls
*the stop is a little slower in the lagging strand primase than the leading stand primase, but it is still pretty quick overall |
|
|
Term
|
Definition
Initiates the formations of phosphodiester bonds that seal the fragmented synthesis strands
Slow stop: elongation continues but the joining of fragments is affected |
|
|
Term
|
Definition
Unwinds the double helix near the replication fork
Quick stop: fork cannot open and replication fork movements stop |
|
|
Term
[image]
what are the parts of the holoenzyme? |
|
Definition
A- holoenzyme core
B- T (tau) subunit
C- Sliding DNA clamp holder
D- Sliding DNA clamp |
|
|
