Most undergraduate chemistry lab courses run a bit like a cooking lesson: Combine ingredients in the prescribed amounts according to the recipe. Heat, mix or shake as needed. Everyone knows what the final end product will be, since the experiment has been done countless times in countless labs.
Jen Heemstra’s undergraduate lab course is different. Just as in actual scientific research, neither the students nor the professor are totally sure what the outcome of the experiments will be, since together they are breaking new ground.
Heemstra’s Advanced Chemical Biology Lab course (CHEM 5750) is a course-based undergraduate research experience — a “CURE.” The class is a win-win for researchers and students. Professors get a boost in their research capacity and a chance to get more students on the bench as undergraduates. Students get training and time in a research lab and a chance at publishing their original contributions to the scientific community.
“I tell the students: ‘Nobody has ever done this experiment before,’” Heemstra says. “’Nobody knows what the answer to this problem is. If we can get good data, we can publish that and you will have contributed knowledge to the scientific community.’ That’s usually when I see the eyes light up.”
Building the CURE
CUREs can be found in many institutions, so many in fact that an online marketplace, CUREnet, exists to pair projects with interested CURE instructors. Haverford College in Pennsylvania has been offering a CURE-like experience called “Superlab” for 50 years. The concept of a CURE fulfills a need for science departments: Most wish they could give every undergraduate a laboratory research experience, but lack the lab capacity to do so.
Heemstra’s class can accommodate up to 60 students in five sections. The class is offered once per year as a seven-week, half-semester course. Students attend two hours of lecture per week, and spend eight hours in the lab. Initial lectures mimic the first conversations between a researcher and a student on joining a lab, and cover safety, techniques and background reading.
Erin Price, who is pursuing a five-year bachelors/master’s degree in chemistry, took Heemstra’s class in 2014, the first year it was offered. “[Dr. Heemstra] brought in papers,” Price says. “It wasn’t from a textbook everyone’s been using. This was an unstudied topic.”
Students are divided into teams, and each team tackles a part of the overall scientific question the class is collectively working to solve. As the course progresses, lectures take on the flavor of lab group meetings, as students discuss their challenges and successes.
“The level of peer-to-peer mentoring is phenomenal,” Heemstra says. “Often I’ll go into the lab and see one set of students struggling, another set helping them out, and everyone checking each other’s calculations. If one group can’t get something to work, another will say ‘follow us around, watch what we do and we’ll watch what you do.’”
Heemstra also integrates career exploration into her lectures. She tells students about her life as a chemist in academia and also invites chemists from industry to talk about their own career paths. “A lot of students interact with a lot of faculty members, but yet they never get to really hear how we got this job and what our job is like,” Heemstra says.
In the 2014 CURE, students delved into the field of biorthogonal chemistry, in which a molecule reacts only with a specific part of another complex molecule. This type of chemistry finds application in precisely attaching chemical tags to proteins or DNA molecules. Heemstra noticed that for a certain set of popular reagents the rate of reaction under biological conditions was not known. As yet, no one had done an in-depth analysis of the reaction kinetics. Price’s part in the work was to run the reaction in varying concentrations of the organic solvent dimethyl sulfoxide.
The students also tried the reaction in micelles, small spherical arrangements of molecules that allow a hydrophobic substance (think oil) to mix with water. The reaction ran faster in micelles, and Heemstra submitted part of the group’s work for publication in Bioconjugate Chemistry. Reviewers of the paper wondered if the micelle-catalyzed reaction would work with a biological molecule, such as DNA. Heemstra went to the lab, tried the reaction on a piece of DNA, and recalls thinking, “That’s the experiment we’ll build the whole second year curriculum off of.”
So, 2015’s CURE continued 2014’s work, exploring micelle catalysis at different points on the DNA structure. Meanwhile, the group’s paper caught the attention of researchers at Rockefeller University, who independently arrived at the concept of micelle catalysis at about the same time. Rockefeller researchers are now working with Heemstra to develop the third year curriculum, which will explore how reaction rates vary at different places for proteins embedded in cellular membranes.
Continuing the work
Because the pace of science doesn’t always line up neatly with semester calendars, Heemstra offers students the opportunity to continue with her lab for an extra semester to complete their work. Because the students are already trained in lab techniques and procedures, she can accommodate more undergrads in her lab than if she had to train them from scratch. About 10 percent of students take that opportunity each year, and Price was one of them.
She is still with Heemstra’s lab, now working on another project for her master’s thesis. Price says that her CURE experience definitely factored in to her decision to pursue the bachelor’s/master’s program. She had heard about the five-year program, but hadn’t given it much thought. “I started doing research more and listened to what all the other grad students were doing. It was a cool experience and I wanted to do that,” Price says. She plans to pursue a doctorate at some point as well.
Heemstra acknowledges that her lab course doesn’t teach as many techniques as a traditional cookbook lab experience, but adds that students instead gain the tools to learn new techniques and instruments on their own. Heemstra hopes that her students at the U someday echo the sentiments of Haverford College graduates, who repeatedly and consistently point to Superlab as the highlight of their undergraduate experience.
“That’s where I learned to learn,” they say.