Essay On Agarose Gel Electrophoresis

Background DNA molecules can be too big to analyze through electrophoresis, some they must be cut up into smaller pieces. In order to cleave dsDNA at the specific sites, making sure each fragment contain the desired sequence, restriction enzymes are used. Restriction enzymes can recognize a specific sequence of nucleotide and hydrolyze the bond of the DNA backbone. Hence, the fragments from the same DNA source will also be the same if cleave by the same restriction enzymes. Restriction enzymes will recognize specific palindrome sequence and cleave there. The number of fragments and sizes of the fragments obtained by cleaving the dsDNA are dependent on the restriction enzyme sites and the distance of each restriction enzyme sites from one another. After cutting up the dsDNA into smaller fragments, they usually undergo electrophoresis so data can be obtained. Small quantities of nucleic acid can be detected through agarose gel electrophoresis. Samples with the desired plasmid, DNA loading dye, restriction enzymes, and water are mixed and carefully pipetted into wells on an agarose gel. There will also be a well with a DNA marker to help determine the relative sizes of the fragments. A …show more content…
For the P lane, we saw several bands indicating the different forms of DNA. For A lane, it was expected there would be three bands since ApaLI made 3 cuts ---- there was only 2 bands. For the E lane, it was expected for there to be one band at around 5421 bp since there was only one cut by EcoRV. The band appears slightly below the 6 kilobases for the marker so this seems correct. For the N lane, there should have been 4 bands since there were 4 cuts by NaeI. From the gel, only two bands could really been seen. Although, some results were unexpected, the experiment did gave a handle on how to work with plasmids and subjecting them to different restriction enzymes. It was also helpful in learning how to analyze the