Math and Chemistry: Volatile Combination?

             This week, I went to the lab of Claudio Rossi, Silvia Martini, Maso Ricci, and Claudia Bonechi to listen to a presentation on “Effects of Exogenous Ethanol on Fermentative Metabolism of Saccharomyces cerevisiae Investigated by In Vivo C13-NMR and Mathematical Modelling”. The idea of mathematical modelling has always been a source of interest to me, but I have never had too much experience with it in classes. This study encompasses math, chemistry, as well as biology in which each of these components proves to be essential.

            To give a context to this study, researchers were attempting to better understand the metabolism of sugar in order to make ethanol as biofuel. By comprehending the best conditions to produce ethanol, they must look for the fastest metabolized products. Glucose is the most commonly known sugar used in fermentation, but behavior when using xylose as the sugar was put to question in this study.

            In order for products to be identified and thus the metabolism process to be documented, Dr. Rossi’s lab used isotopes to tag substrates and analyzed the different products by these tags. This applies directly to the subject we covered in 260 earlier this week. C12 is naturally found in the initial sugars, but specific carbons were replaced with C13. This change allowed for a marker to be seen at each step and a difference in the NMR analyzed.

            Once the process of tagging and analyzing is completed with different combinations of xylose and glucose, the trends are converted into equations that form Energy System Diagrams. These diagrams are composed of symbols that communicate and map the connections of the results, almost like a different language. Each interaction is given its own equation and its own constant. This system was interesting to me because of the clarity it has in expressing the independence and dependence that the sugars and their intermediaries have on the process as a whole. Factors such as glucose catabolism, production of ethanol, cell viability and ethanol feedback inhibition were fit into this system.

            Chemists see a lot of math in their work, but Dr. Rossi’s study took it one step further in explicitly using mathematical application in furthering his assessment of yeast metabolism. I look forward to see what new models they create, the results that they glean, and the impact it may have on future biofuel studies.