By Ajay Mehta
Phage Hunting first caught my attention during my campus tour of Johns Hopkins University. My tour guide was extremely excited to share her experiences taking the class and, needless to say, her excitement was infectious. After I chose to attend Johns Hopkins, Phage Hunting was the first class I knew that I wanted to take. Two months later, I stepped into a lab for the first time.
Over the last two months, Phage Hunting has taught me that working in a lab is a mix between excitement and patience. Beginning with direct plating and enrichment, I enjoyed learning and executing different procedures. Then, as I moved on to the lengthy process of streaking in an effort to obtain a pure plaque, I began to experience a new form of excitement despite the repetition of the same procedure. As each streaking day passed, I felt as though I began to become comfortable, faster, and more confident with the procedure. Furthermore, this exciting confidence and comfort with working in the Phage Hunting lab grew as I practiced dilution series repeatedly (due to errors in web calculations and contamination).
This excitement, however, was not alone. Every day in the lab my patience was tested and it continues to grow. Whether it be waiting 15 minutes for the phage to infect M. smegmatis, waiting 20 minutes for the centrifuge to run, or waiting either 2 or 5 days until the next class to check the phage growth in incubated petri dishes, a large portion of working in a lab is being patient in order to successfully complete procedures. Ultimately, I have grown accustomed to waiting and being patient because it is a part of the scientific process.
One of my favorite aspects of my work so far was separating two phage morphologies based on their visual plaque characteristics. From the beginning of my enrichment stage, I had two morphologies: a “fuzzy” plaque that was relatively small and a “cloudy” plaque that was less clear yet larger in size. I enjoyed working on both morphologies simultaneously while comparing the streak plates for each morphology to ensure only one of the two morphologies was present in each lineage of plates. While I ended up only creating the medium titer lysate for the fuzzy plaque, I have saved one of the cloudy plaque plates with the hope that I might be able to return and work with the cloudy plaques again at a later date.
Jumping forward to my current work, I am excited to have created my high titer lysate (HTL). Next class, I will use the plates created through a dilution series of the HTL to determine its titer. I predict that the HTL will have a larger titer than my MTL. I am also looking forward DNA prep and the electron microscopy process, both of which will be new and exciting experiences!