Which prokaryotic polymerase has both 3 to 5 exonuclease activity and 5 to 3 exonuclease activity?
DNA polymerase I
DNA polymerase I also has 3′ to 5′ and 5′ to 3′ exonuclease activity, which is used in editing and proofreading DNA for errors.
Does DNA polymerase III have 5 3 exonuclease activity?
DNA polymerase III (polIII) holoenzyme of Escherichia coli has 3′—-5′ exonuclease (“editing”) activity in addition to its polymerase activity, a property shared by other prokaryotic DNA polymerases. The polymerization activity is carried by the large alpha subunit, the product of the dnaE gene.
Which enzyme has exonuclease activity?
This exonuclease activity is called the proofreading or editing function of DNA polymerase I. Pol I also has a unique 5′ to 3′ exonuclease activity that is required for its DNA repair function.
Does Pol 3 have exonuclease activity?
DNA polymerase III (polIII) holoenzyme of Escherichia coli has 3′—-5′ exonuclease (“editing”) activity in addition to its polymerase activity, a property shared by other prokaryotic DNA polymerases.
Why polymerase has exonuclease activity?
Replicative DNA polymerases possess 3′ → 5′ exonuclease activity to reduce misincorporation of incorrect nucleotides by proofreading during replication.
What is the activity of BST 2.0 DNA polymerase?
Bst 2.0 DNA Polymerase is an in silico designed homologue of Bacillus stearothermophilus DNA Polymerase I, Large Fragment ( Bst DNA Polymerase, Large Fragment). Bst 2.0 DNA Polymerase contains 5´→3´ DNA polymerase activity and strong strand displacement activity but lacks 5´→3´ exonuclease activity.
Is there a 3-5 exonuclease domain in BST?
This cast doubt on the existence of a 3′–>5′ exonuclease function in that enzyme. Four biochemical assays were used to measure exonuclease activities of Bst DNA polymerase I, testing both full-length Bst polymerase I and the Bst large fragment which lacks the N-terminal 5′–>3′ exonuclease domain.
What are the missing motifs in Bst polymerase I?
The Bst polA gene that codes for Bst polymerase I was cloned and sequenced. Comparative sequence analysis showed that all three conserved 3′–>5′ exonuclease motifs found in E. coli DNA polymerase I were missing in Bst DNA polymerase I. This cast doubt on the existence of a 3′–>5′ exonuclease function in that enzyme.
What is the dominant species of thermostable DNA polymerase I?
A thermostable DNA polymerase, the Bst DNA polymerase I, from Bacillus stearothermophilus N3468 was prepared to near-homogeneity. The dominant species of the Bst DNA polymerase I preparation sized about 97 kDa when analyzed on SDS polyacrylamide gels.