Masters Degree Research ThesisDuring my course of study at Clemson University for my Masters in Microbiology, I wrote a thesis on the survival of a certain strain of bacteria during starvation conditions. Research is basically useless without application. What if I told you this research can be applied to understanding how we gain or lose weight? Interested? Read on.

The abstract of the research gives the gist of what the research is about and how it could apply to our diet and nutrition thinking process. If you have some background in genetics you could read the abstract below and get a better idea of how the experiment was conducted. Here, however, is the short version. We grew some bacteria called P.putida and then starved them for months. After which we studied and observed carefully what happened to them over a period of starvation.

Within 3 days with no foods except water and salts, the bacteria shrank in size by more than 50% and some even changed from rod-shaped to little round circle shapes or cocci. This phenomenon was no big surprise since we see that in humans who go on diet or fast. What would you expect to happen to those who go on a diet and then stop their diet and return to their regular routine? Well, in the case of our bacteria, after starving them for days, weeks, and even months, they manage to survive. When we added little drops of food, the cells actually grew abnormally large, up to about twice its original size!

Have you ever heard of people skipping meals and then at the end of the day, eat a heavy dinner or supper and wonder why they put on a lot more weight than those who eat meals regularly? You see, it is our body’s job to make sure we have enough food or fuel to efficiently do what we need to do. However, skipping meals send the body into a starvation mode, which sets the body to increase storage capacity when the next meal arrives to ensure survival should there be a famine condition again. This famine situation happens when we skip meals. So the next time you skip meals, especially when you are hungry, consider getting a light snack instead if you don’t have time for a meal or have not much appetite.

Research Abstract
A Pseudomonas putida strain PaW 164 bearing the TOL plasmid pWWO encodes the degradation of toluene, m-, p-xylene, 1,2,4- trimethylbenzene and m-ethyltoluene. The strain was grown in toluene and placed in carbon-free minimal salts media. Viable counts were determined by their abilities to form colonies on m- toluate, recovery medium and benzoate plates. No loss of plasmids were found after 2 months of starvation, but starved cells showed increased sensitivity to growth on toluate and benzoate. In addition, plate counts showed that after spiking with toluene, the cells population increased by about 10-fold above the pre-spiked population count. Viable plate counts on m-toluate, recovery and benzoate dropped rapidly to the pre-spiked counts.

Direct total cell counts did not show any significant change in the total population of cells up to 80-days of starvation. Induced cells were sampled at increasing starvation times and assayed for their potential to mineralize radioactive UL-14C-Toluene or UL-14C- glucose. The rate of mineralization of 14C-toluene was highest at the start of starvation and decreased with starvation. In contrast, the potential to mineralize glucose was lowest at the onset of starvation, reaching a maximum after three days of starvation, and decreased with further starvation. After the 3 days of starvation, the cells shifted their metabolism to better mineralize glucose. After which, the rate of glucose mineralization showed similar decreasing trends as with toluene mineralization.