DNA polymerase III is the main DNA-synthesizing enzyme in bacteri...

Question

DNA polymerase III is the main DNA-synthesizing enzyme in bacteria. Describe how it carries out its role of elongating a strand of DNA.

Accepted Answer

Hi, everyone. Let's look at our next problem. It says during bacterial chromosomal DNA replication, an enzyme known as blank is responsible for catalyzing the elongation of DNA chains. And our choices are a DNA polymerase two. Choice B DNA polymerase, three hollow enzymes. Choice C DNA ligase or choice drn a polymerase three. So we're talking about in DNA replication, the actual kind of meat of the process, the elongation of the DNA chains. So adding basis to the new chain and the enzyme responsible for that is choice B DNA polymerase three hollow enzymes. Let's look at our other choices to understand why they're not correct. Choice. A is a DNA polymerase, but it's a DNA polymerase two. And it's primarily involved in repair rather than synthesis of a new strand. So it does have five prime to three prime plym activity or um adding on new base pairs, but it also has uh three prime to five prime exo activity. So it can excise, wrongly added base pairs and repair mistakes, but that's not what we're looking for. So that's not correct N to C DNA ligase. Um as evidenced by its name ligase, it has the ability to join breaks in a DNA strand. And of course, it has a really key process in DNA replication in joining together all the Okazaki fragments that make up the lagging strand during DNA replication. But that's not what we're looking for. So choice C isn't our answer. And then finally, choice DRN a polymerase three. Well, we might get misled by the polymerase three there, but this is RN a polymerase. So this is involved in the synthesis of Trnas five srrnas and other small specialized RN A molecules but not what we're looking for. So choice D is not correct. So again, during bacterial chromosomal DNA replication, an enzyme known as choice B DNA polymerase three hollow enzymes is responsible for catalyzing the elongation of DNA chains. See you in the next video.

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DNA polymerase III is the main DNA-synthesizing enzyme in bacteria. Describe how it carries out its role of elongating a strand of DNA.

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Overview of DNA Replication practice set