I am a graduate student doing Masters in Industrial Chemistry majoring in Biotechnology. Currently my work deals a lot with genetics. Plasmid isolation is what I am doing now. I have very little knowledege in this and therefore I have to catch up as soon as possible on the theoretical part of my work.
I have done the isolation of the plasmids and run the agarose gel electrophoresis. The first time was a total failure as even the DNA ladder was not showing anything under the UV illuminator.
The second trial was partly a success as the plasmid for pUC19 was visible on the gel without digestion. The result shown that it was about 1.5kb. However, according to the source, pUC19 was supposed to yield plasmids as big as 3.1kb. Why is it that I only obtained results at 1.5kb?
My strain did not show any plasmids at all. According to literature, the size should be about 23kb. I used Kady and Liu method for plasmid extraction. What could have happened?