Chemistry faculty across all courses have debated as to whether or not labs should be coupled and lecture synchronous. I acknowledge that there are advantages and disadvantages to both synchronous/coupled and asynchronous/decoupled labs; however, I assert that a full-semester multi-week lab experience most importantly translates to the optimal student interest and retention of the material. A full-semester lab semester experience can also be used with either a synchronous/coupled or asynchronous/decoupled lab pedagogy. In my biochemistry courses, I recently developed a full-semester lab that is approximately synchronous with the material learned in lectures. Herein, students work in small groups of 2-3 and are tasked with purifying and characterizing both HRP and HSA from a solution of proteins (HRP, HSA, lysozyme, and myoglobin) with the long-term goal of using pure HRP for a kinetics experiment and pure HSA for a ligand binding experiment. Initially, students determine the properties of their proteins such as pI, molecular weight, and molar absorptivity using Expasy and the Protein Data Bank. Students then purify HSA initially by anion-exchange chromatography since its pI is much lower than the other three proteins. Then, students use affinity chromatography (conA resin) to purify HRP from the other proteins in a second step of purification. After purification is complete, they quantify the amount and purity of their proteins by UV-Vis spectroscopy and SDS-PAGE gel electrophoresis. With HRP, students carry out a UV-Vis kinetics experiment in the presence and absence of an inhibitor to determine the mode of inhibition as well as the approximate KI. With HSA, students screen for ligand binding and estimate the Kd of ligands to HAS using Nuclear Magnetic Resonance (NMR) spectroscopy. Following the completion of the lab, students present their results in a 15–20-minute presentation during the final week of the lab. These presentations give students experience with data analysis, oral skills, and also help prepare students for their final exams. Students are also individually assessed throughout the semester on their understanding of the lab throughout the semester. At the end of the semester, it was found that most students demonstrated mastery and improved retention of the biochemistry learning outcomes that were emphasized in the lab. Ultimately, I hope more faculty consider multi-week labs instead of weekly labs, particularly in upper-level courses.

Rethinking biochemistry lab: A lecture-synchronous full-semester lab in protein bioinformatics, purification, characterization, and experimentation

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