Blog #3: Progress and Reflection

Recently my research lab has unfortunately experienced contamination of the machinery responsible for creating the NGM plates used in my project. The machinery was contaminated with E. coli, which is the bacteria used in C. elegans research so fortunately the source of contamination was discovered. While the equipment was being sterilized, my project consisted of increasing amounts of literature review. I wish to understand the nematode life cycle and metabolism as best as I can, as well as known interactions between the worm and M. tuberculosis. One paper, entitled “The nematode Caenorhabditis elegans displays a chemotaxis behavior to tuberculosis-specific ordorants” has given major insights into the way the nematode reacts to specific volatile organic compounds (VOCs) produced by M. tuberculosis. The researchers plated a sample of worms onto a plate containing a sample of a known VOC produced by the bacteria as well as a control substance where the effect on the nematode is known. The behavior of the nematodes were then tracked for an hour. The data consisted of reactions to different concentrations of four know VOCs as well as a calculated chemotaxis index value. A follow up experiment I plan on performing is observing the effect the VOCs have on nematodes lacking the gene responsible for olfaction.

Working with Dr. Marcello has been an amazing experience. Fortunately our schedules are very compatible so we are able to meet very frequently. Any questions that arise while I’m in lab are quickly answered and serve as a fantastic learning experience that will assist me in my future career. Dr. Marcello has also ordered C. elegans mutants, one of which lack the daf2 gene and the other will lack a key gene in the olfactory mechanism. These mutants are key to my project and I cannot wait to begin experiments.

I am fortunate this semester to have had the opportunity to submit a research abstract to the Eastern Colleges Science Conference. Attending this conference will serve as an experience opportunity that will aid me in my career as well as a catalyst for my research.

Blog #2: Working with C. elegans

In order to perform research in a scientific field, you must have extraordinary patience and expect the unexpected. I had the pleasure of learning this lesson this semester navigating the trials and errors of my experiments. In order to begin the extent of my research, I must first prove that the nematode C. elegans will ingest the bacteria involved in my study. To do this, I performed several feeding assays. This entails placing equal amounts of E. coli, the nematode’s bacteria of choice, and the experimental bacteria on opposite sides of a NGM (nematode growth medium) plate. I then placed a sample of worms into the middle of the plate and monitored them for 4 hours, checking the movement of the worms every half hour. Two plates were made for each experiment for accuracy. Although tedious, I was able to observe to which side of the plate the worms traveled and if they preferred one bacterium over the other. It may sound extremely simple, but nevertheless errors were encountered. For example during my last experiment, the worms did not make any significant movements and therefore I was unable to detect any preference for either bacterium. This raised many questions, especially since I had followed the same procedure as previous experiments. I am currently looking into this event. I also found that maintenance of the worms before performing the experiment requires precise timing and ensuring you have enough worms to place on each plate. Dr. Marcello is extremely helpful in this aspect due to his extensive knowledge of C. elegans.

Half way through the semester, Dr. Kelly was able to order a mutated strain of the experimental bacteria that contains a plasmid causing it to fluoresce. This was a huge step in my research because it would allow me to visualize the bacteria in the worm gut and observe how it interacted with the intestinal epithelia. Unfortunately, an error occurred in growing the mutated bacteria and we were unable to use the cultures. I believe the organization from which we received the bacteria recommended the wrong antibiotic to include in the cultures, which was insufficient in keeping the bacteria alive. We are currently in contact with the organization to receive more bacteria as well as updated procedures. This was definitely a setback in my research, however it taught me the importance of maintenance of the organisms I’m working with as well as performing extra research to understand why I am performing such procedures.

Effect of infection of M. avium on C. elegans Blog #1

The title of my project is Mutations in DAF-2 pathway affect the immune response in C. elegans when infected with M. avium. Caenorhabditis elegans is a model organism for studying infection with Mycobacterium avium due to the worm’s transparent, streamlined body as well as the similarities between its immune response to that of humans due to similar epithelial intestinal cells. The purpose of my research is to study the immune response in C. elegans from infection with M. avium. The DAF-2 pathway is involved in both immune response and aging. Worms genetically engineered to not produce the proteins involved in the DAF-2 pathway will be created and infected with the bacteria to study exactly how these proteins protect the worm from infection. The results from this research will give helpful insights to how homologous proteins in humans work to protect the body from M. avium infection.

What I hope to take away from this project is a better understanding of the research process and how to balance between academic work and personal work. I am passionate about performing research and I’m extremely excited to produce data from an experiment completely created by myself and to be able to showcase this data to the scientific community.