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Department: Microbiology More Information
A day in the life of an undergrad in the Helmann lab…The Helmann lab performs research on the Gram-positive soil bacteria Bacillus subtilis. The lab is, which has about 10-15 people working in it, is split into two halves: one dealing with the cell wall and the other working on metal homeostasis. I work in the section that studies metal homeostasis, particularly manganese and magnesium homeostasis. My current project involves determining which genes code for manganese and magnesium ion transport channels. First we use a PCR reaction to knock out specific genes with an antibiotic cassett. The DNA we create here is then transformed into a wild-type or, in order to make double and triple mutants, a previously mutated strain. These strains are then inoculated into media that contains varying concentrations of the metal ions. After incubating them overnight, I then read their optical density to measure how much they’ve grown. What we are looking for is a strain that will only grow if the metal concentration is much higher than that needed for the wild-type strain to grow. If the bacteria will only grow in the media where the metal concentration is high enough for diffusion to occur, we know that we’ve knocked out all of the genes that code for those metal transporters.For anyone looking to work in this lab, I would strongly recommend taking genetics (BioGD 281) and microbiology with its lab (BioMI 290/291). Since you are running a lot of PCR reactions, it’s important to know how PCR works and how to read a genetic sequence and create the necessary primers for your reaction. You should also be familiar with bacterial genetic techniques, especially transformation. Other lab skills involve gel electrophoresis, media preparation and for some projects, protein techniques such as Western blots are employed. You also need good planning skills because many experiments involve bacterial growth and cannot be completed in one day. Dr. Helmann himself is very concerned with publishing results. He is very up to date with the printed literature and works closely with the senior members of the lab to get their work published. He even encourages the younger grad students and undergrads to approach their projects with a “how will I write this up in a paper?” attitude. This is an extremely important way for any researcher to think. Working over the summer and working during the school year are two entirely separate things. Over the summer, you can dedicate your life to your research, and that’s what is expected. You can attack the question from multiple angles and have several experiments running at the same time. But during the school year, they understand that you’re primarily a student and are very flexible. I sat down with Dr. Helmann and discussed my schedule before the semester started and we worked out a lot of methods so that I could come in during the evening, set my experiment up and then come back the next day to read the results. Even though it adds a lot of hours on top of my course work, working in the lab is a very beneficial experience. A Hughes Scholar Guide to Doing Research in the Helmann LabFinding a research lab can be extremely challenging. When I began looking for a lab to work in, I searched for that rare combination of intellectual curiosity and friendliness. In the Helmann lab I was lucky to find both of those qualities in abundance. In this lab, I am working on characterizing the function of various phospholipids that make up the cell membrane in the model Gram positive bacterium Bacillus subtilis. In order to do this, the lab has systematically created (using PCR methods) a collection of mutant strains of B. subtilis that lack an enzyme required in the pathway to synthesizing a particular phospholipid or combinations of phospholipids. Our goal now, and what I have been working on, is to observe the differences in physiology and behavior of these mutants as compared to the wild type when placed in a variety of conditions. One way to assay these differences is to generate growth curves of these mutants in different types of media (complex and minimal) and compare their growth behavior to the wild type bacterium. In another assay (aptly called a Sporulation Assay), it is possible to compare the abilities of these mutants to generate resilient endospores by a process called sporulation (a particular survival mechanism). In the coming months, I hope to confirm the data I have collected thus far and begin changing other environmental conditions to see the response of these mutants. Ultimately, our goal in performing this research is to gain a better understanding about the bacterial cell membrane so we can perhaps, in the future, apply this knowledge to fine tuning the methods by which bacterial infections are treated. |