DNA

Week 7

In molecular biology on Monday and Wednesday, Dr. Peng discussed DNA damage and repair mechanisms including nucleotide excision repair, non-homologous end joining, and translesion synthesis. For the honors paper in this class, I decided to write about the molecular biology of preeclampsia, as I have previously researched the pathophysiology of the disease. In biochemistry, Dr. Popescu reviewed DNA technologies beginning with the mechanisms of cloning. On Thursday, she continued with reviews of polymerase chain reaction amplification of DNA, electrophoresis separation of DNA, and DNA genotyping.  The second part of the lecture was about eukaryotic gene expression in bacteria.

In bacterial physiology on Tuesday, Dr. Roberts handed back quizzes and midterm grades, answered any questions about any lecture material, and listed important topics for the test on Tuesday. On Thursday, four groups presented papers titled Antimicrobial effects of silver nanoparticles, Capsule switching and antimicrobial resistance acquired during repeated Streptococcus pneumoniae pneumonia episodes, Effects of fermented sumach on the formation of slime layer of Staphylococcus aureus, and Membrane lipoteichoic acid of Streptococcus pyogenes and its stabilized L-form and the effect of two antibiotics upon its cellular content. These papers in addition to all the others presented in class will be on the test on Tuesday, so I have read through the papers again during my studying for the test.

 

In bacterial genetics lab on Friday, we selected colonies that had the recombinant plasmid. The microbial DNA, if taken into the plasmid, would have disrupted the gene for X-gal utilization. When transformed into E. coli that were plated on an agar with X-gal, the E. coli with non-recombinant plasmids would grow into blue colonies, since they could utilize the X-gal. The E. coli with recombinant plasmids, since they could not utilize X-gal, grew into white colonies. My lab partner and I had fewer colonies than the rest of the class, so we selected all our colonies, while the rest selected white colonies.