AL's+Milestone+-+Linearized+DNA

By using the restriction enzymes on plasmid DNA, we create **linearized DNA**. First of all, it is important to note what an enzyme even is. An **enzyme** is a kind of **protein** (organic molecule made of **amino acids**) that accelerates or catalyzes chemical reactions. In this project, restriction enzymes are used. **Restriction enzymes** are enzymes used to cut the DNA at its backbone, between the base pairs. There are many different types of restriction enzymes, but the one I'm using is kp I.

One problem I encountered in my project was how small the circular DNA plasmids were as seen in the AFM image. Because of this, it was hard to gauge in what ways the APTES and N-Trimethoxysilylpropyl-N,N,N-trimethylammonium chloride affected the DNA. What was suggested to me was to use **restriction enzymes** which would cut the DNA plasmid at a certain point which would cause it to relax and spread out. This would then enable me to more clearly see the changes that the monolayers caused in the DNA. This image is from [|www.geneservice.co.uk].



This image shows the puc 19 circular DNA plasmid's restriction points for certain enzymes. Depending on the enzyme and plasmid you choose, the enzyme will cut the DNA at a different point. The **kp I enzyme** cuts the DNA plasmid at the top right corner of this image, where you see a blue list of enzymes that cut at that specific point. I am trying to make the DNA bigger, or longer, when appearing under the AFM. Under the previous circumstances, the plasmids were coiled and small, not very visible. By cutting the DNA with a restriction enzyme, the circular plasmid would unravel, making the DNA easier to see. This new shape of the DNA would also make it easier to see the effects of the APTES and other solutions on the physical properties of the DNA.

Next Milestone - Do Enzyme Digestion of DNA Process