DNA polymerase I (pol I) processes RNA primers during lagging-strand synthesis and fills small gaps during DNA repair reactions.May 26, 2011
What is the function of DNA polymerase 1 quizlet?
DNA polymerase I is an enzyme involved in prokaryotic DNA elongation and repair. It has 3 activities: 5'-3' polymerase activity (synthesis), 5'-3' exonuclease activity (repair and removal) and 3'-5' exonuclease activity (proofreading).
What is the function of DNA polymerase 1 and DNA polymerase 2?
DNA polymerase I functions to fill DNA gaps that arise during DNA replication, repair, and recombination. DNA polymerase II also functions in editing and proofreading mainly in the lagging strand (Kim et al. 1997, Wagner and Nohmi 2000). DNA polymerase III is the main replicative enzyme.
What is the function of DNA polymerase I and III?
In Escherichia coli, five DNA polymerases have been found and designated as DNA polymerase I–V, in order of their discovery. The main function of the third polymerase, Pol III, is duplication of the chromosomal DNA, while other DNA polymerases are involved mostly in DNA repair and translesion DNA synthesis.
What is the role of DNA polymerase 1 and 3 in DNA replication?
DNA polymerase 3 is essential for the replication of the leading and the lagging strands whereas DNA polymerase 1 is essential for removing of the RNA primers from the fragments and replacing it with the required nucleotides. These enzymes cannot replace each other as both have different functions to be performed.
What does DNA polymerase 3 do simple?
Primase synthesizes RNA primers complementary to the DNA strand. DNA polymerase III extends the primers, adding on to the 3' end, to make the bulk of the new DNA. RNA primers are removed and replaced with DNA by DNA polymerase I.
Why is DNA polymerase 1 needed?
The physiological function of Pol I is mainly to support repair of damaged DNA, but it also contributes to connecting Okazaki fragments by deleting RNA primers and replacing the ribonucleotides with DNA.
Is DNA polymerase 1 used in PCR?
Like DNA replication in an organism, PCR requires a DNA polymerase enzyme that makes new strands of DNA, using existing strands as templates. The DNA polymerase typically used in PCR is called Taq polymerase, after the heat-tolerant bacterium from which it was isolated (Thermus aquaticus).
Why is DNA polymerase I not used in PCR?
As the polymerase binds to DNA, it adds nucleotide in the direction of 5' to 3'. Unfortunately, because it disables at a higher temperature, DNA Polymerase is not suitable for a type of replication called Polymerase Chain Reaction (PCR).Mar 17, 2020