Which of the following enzymes has proofreading activity?
DNA polymerases
What are the three enzyme activities present in E coli DNA polymerase I?
Pol I possesses four enzymatic activities: A 5’→3′ (forward) DNA-dependent DNA polymerase activity, requiring a 3′ primer site and a template strand. A 3’→5′ (reverse) exonuclease activity that mediates proofreading. A 5’→3′ (forward) exonuclease activity mediating nick translation during DNA repair.
What enzyme performs Decatenation in E coli?
The effect of supercoiling on unknotting was also investigated in vitro by comparing unknotting of supercoiled and non-supercoiled DNA molecules by Topo IV (39), i.e. the enzyme that is believed to be responsible for DNA unknotting and decatenation of DNA in E. coli.
Which of the following enzymes is the principal replication enzyme in E coli?
DNA pol III
How many numbers of replicon is found in E coli?
A total of 1,015 E. coli isolates were examined for the presence of the 18 plasmid replicon types using the simplified three-panel multiplex PCR protocol.
Which protein is required for connecting Okazaki fragments?
DNA ligase
What is meant by Replicon?
A replicon is a DNA molecule or RNA molecule, or a region of DNA or RNA, that replicates from a single origin of replication.
What is a replicon in DNA?
A segment of the eukaryotic genome that contains several genes and is replicated as a unit from a single origin. replication is bi-directional; its boundaries are the points where replication from one origin meets the replication fork which advances from the opposite direction.
Is plasmid a replicon?
The replicon is comprised of the origin of replication (ori) and all of its control elements. The ori is the place where DNA replication begins, enabling a plasmid to reproduce itself as it must to survive within cells.
What is replicon and its significance?
It is critical that all the DNA in a cell be replicated once, and only once, per cell cycle. Jacob, Brenner and Cuzin defined a replicon as the unit in which the cell controls individual acts of replication. The replicon initiates and completes synthesis once per cell cycle. Control is exerted primarily at initiation.
How do plasmids differ from chromosomes?
Plasmid. A plasmid is a small, often circular DNA molecule found in bacteria and other cells. Plasmids are separate from the bacterial chromosome and replicate independently of it. They generally carry only a small number of genes, notably some associated with antibiotic resistance.
What is the replication bubble?
A replication bubble is an unwound and open region of a DNA helix where DNA replication occurs. Helicase unwinds only a small section of the DNA at a time in a place called the origin of replication. In eukaryotes, there are several origins of replication on each chromosome.
What is a replicon quizlet?
replicon. unit of DNA in which replication is fired once per cell cycle. origin, terminus region.
What is the function of Tus protein quizlet?
What is the function of Tus protein? It allows the replication forks to be stopped by the ter sites in both orientations. Although the replication fork moves 10x faster than RNA polymerase, the Tus protein acts to make it move even faster. It stops transcription when the replication machinery is approaching.