I can’t believe it’s (almost) been a full academic year as a visiting professor at St. Mary’s College of California! Today’s the last day of classes and then it’s just finals (and finalizing assignments) for the students, and then grading (lots and lots of grading…) for me. I have had an amazing time these last 10-ish months, thanks to amazing students, fantastic and supportive colleagues, and the awesomeness that is biochemistry. There were definitely ups and downs, and some rocky points as I worked to find my stride, but I really feel like I’ve matured a lot as a person and a teacher. It’s weird - I can notice a real change in my sort of internal voice, finding myself being a lot more deliberate and teacher-ish in how I approach explaining things (including trying to talk slower!) bit.ly/oneyearteaching
Although I love almost all of biochemistry, I somewhat surprisingly found myself most enjoying teaching metabolism. I say “somewhat surprisingly” because metabolism was always one of those topics that scared me because it just seemed so complex (& I never took an in-depth metabolic biochemistry course, learning mostly on my own instead). Approaching metabolic biochemistry after years of scientific training really helped me appreciate it in a whole new light. I realized that, similar to o-chem, there are lots of reactions & mechanisms - but, if you focus on the core themes & principles & are able to follow diagrams, you can really intuit & induce a lot!
Speaking of metabolism… although in class we focus mostly on human metabolism, my research interests have actually pulled my lab & I towards microbial metabolism. You might remember I had planned originally to study translation and develop cheap ways to do so. Unfortunately, despite the hard work of my independent research students Haley and Bobby, that project wasn’t really working out. So, just like metabolism does, we adapted!
Through various channels in the undergraduate biochemistry education community (including at the ASBMB’s national DiscoverBMB conference I had the privilege of attending), I learned about the Malate Dehydrogenase CUREs community. More on the CUREs aspect in a minute, but let’s start with the malate dehydrogenase part. Malate dehydrogenase or, as its friends call it, MDH, is a central metabolic enzyme throughout all life forms. If the name rings a bell, you might be recalling its role in the citric acid cycle (TCA/Krebs), or maybe even its job shuttle electrons into the mitochondria in the malate aspartate shuttle, or perhaps its role in getting carbons from the TCA into gluconeogenesis. MDH also helps w/redox balance (think oxidative stress protection) & helps coordinate a lot of things.
Different organisms have MDH’s w/conserved functions but different cool adaptations and thus there are lots of undergraduate teachers who study it with their students - both as their own research lab focus & as part of Course-based Undergraduate Research Experiences (CUREs), which are authentic research experiences that take place as part of the lab portion of a class. This CUREs format lowers the barrier to access to research and helps all students get a flavor of how cool it can be - perhaps even helps them see themselves as scientists!
This is all my long-winded way of saying that, wanting to get involved, I started thinking about unique MDH angles. And wanting to find a little niche. Ideally, it would also mesh w/my (modest) ambition to help the world. I proposed several angles to my students & Haley was the one who really jumped on the “bioremediation” aspect. Bioremediation refers to using living organisms (such as bacteria or plants) to clean up the environment. I found some potential links between MDH & the bioremediation of heavy metals. And, then we were off. First step, finding some bacteria that could perform an environmental “detox.”
Following some literature leads (and after several dead ends), we came across the bacterium Bacillus safensis, which is known to often inhabit extreme environments - in fact, the “first” strain of it was originally discovered in a NASA facility! We obtained some uncharacterized strains from a public collection, & started screening them for their ability to reduce levels of the highly-toxic heavy metal chromium VI (Cr(VI)) to its much less-toxic form, Cr(III). And, Haley & Bobby found some! Using a cool colorimetric (color-based) assay (test) in which you mix a chemical called DPC with a solution and any Cr(VI) present will react with the DPC and make a purple product. One of the most exciting moments in the lab was when Haley added the DPC to the Cr(VI)-spiked media (broth) the bacteria had been growing in & saw no color change! Indicating the bacteria had removed all the Cr(VI)!!!!
Unfortunately, these findings came right at the end of the semester. Thankfully in time for Haley& Bobby to present at SMC's student research symposium*, but not in time for much follow up. Finished in comments