Question

Please describe the overall mechanism for DNA polymerase function as discussed in class. What is the role of conformational changes in insuring substrate specificity? Do DNA polymerases share a universally conserved mechanism?

Answer 1

DNA polymerase catalyze template dependent DNA synthesis during genome replication and repair. These enzymes are responsible for preferentially binding and incorporating a nucleotide, from a pool of chemically and structurallysimilar molecules, that correctly base pairs with the appropriate templating base. It is composed of 2 domains. each domain contributes an enzymatic activity during repair of simple base lesions.

DNA polymerase beta has served as a model enzyme for studying fundamental task, providing detailed understanding of the events during substrate selection. DNA polymerase is essential for DNA replication and usually work in pairs to create two ideentical DNA strands from a single original DNA molecule.

In eukaryotes there are 5 families of DNA polymerase.

DNA polymerase adds nucleotides to the three prime end of a DNA strand, one nucleotide at a time.Every time cell divides, DNA polymerases are required to help duplicate the cell's DNA, so that a copy of original DNA molecule can be passed to each daughter cell.

Before replication can take place, an enzyme called helicases unwinds the DNA molecule from its tightly woven form, in the process of breaking the hydrogen bonds between the nucleotide bases.

The pairing always occurs in specific combinations with Cytosine along with guanine, and thymine along with adenine forming two seperate pairs, respectively. so the newly forming strand in 5 prime to 3 prime direction.

YES DNA polymerases are highly conserved structure which means their overall catalytic subunits vary little from species to species, independent of their domain structures,They share universally conserved mechanism.