PCR and sequencing HMY7

Hello readers! (of which I am sure there are many)

Well, I have reached the end of the second week of summer research. So far, I have been working on the project that I have been on since the Spring semester. It isn’t my allantoin pathway work yet, but it will lead into that project, so I am excited to finish up this stuff so I can look into the allantoin research. I have been doing PCR, PCR, and some more PCR! I did PCR for all of the genes previously found to be significant to plastic adherence for the strain HMY7. In the Spring, I worked on the genes in the strain HMY355. PCR proved…difficult. Many of the genes in these two strains are particular to say the least. So, I ended up with a bunch more PCR hours under my belt, but only about 50% of them worked. But! That’s okay. I pushed on and did PCR clean-up for the genes and the corresponding segregants (high and low plastic adherence segregants) that did work. I then did a big push for sequencing and just submitted the samples. Hopefully the sequences will be back in a few days and I can begin analysis! What I will be looking for is a systematic difference (an SNP or change in allele) between the high and low segregants because this means that that difference is probably crucial to determining whether or not the segregant will have high or low adherence.

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Defrosting, Detours, and a Debrief on Evolution

Last week was my first week of summer research. I was actually very excited to come back to campus. Relaxing at home is wonderful and much needed after finals, but with all the time in the world on my hands I started to get a little antsy. At the end of the semester, I paused my experiment by storing my yeast populations in glycerol and freezing them. Freezing the yeast puts them in a dormant state. When I returned for the summer, I knew I would be able to start exactly where I left off. For the first couple of days, all I did was prepare myself to start evolving again by getting all my equipment ready. I grow the yeast in glass tubes filled with evolution medium, basically sugar water. I spent a good portion of Monday autoclaving (sterilizing) and washing old tubes, making evolution medium and filling up clean tubes with it. At the beginning of last week, all but one of the autoclaves in the ISC was broken, so it was quite an adventure having to go back and forth to the third floor to get all my work done.

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Identifying the Genetic Underpinnings that Drive the Transition of Commensal Yeast Microbes to Opportunistic Pathogens

The unique relationship between humans and commensal microbes is a critical component of human health. Recent studies have shown that this relationship can be altered by the microbial evolution of social behaviors. Biofilms are complex microbial communities that can be found in a variety of environments. The formation of biofilms plays a vital role in driving the virulence of many microbial pathogens that are capable of infecting humans, and has allowed these organisms to survive in hostile environments. In fact, many commensal microbes have evolved into virulent, opportunistic pathogens through this mechanism. Currently, there exist a number of studies on the genetic basis underlying this transition among bacterial species in clinical settings. However, research on the evolution of virulence in medically relevant fungal species is lacking. For my research project, I intend to investigate the genetic underpinnings that result in the transition of a commensal microbe to an opportunistic pathogen by tracking the genomic changes in particular phenotypes that play a role in virulence. Specifically, I will determine whether the genetic variants uncovered in  S. cerevisiae yeast strains isolated in a clinical environment are the same genetic variants that are selected for when virulence evolves de novo in the lab.

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