Several agencies and advisory committees in the United States have highlighted the need to increase the number of STEM professionals as it boosts both the nation’s economic competitiveness and drives technological advancement. Recommendations to increase interest in STEM include replacing demonstrative laboratories with guided research experiences and promoting collaboration between educators and larger research institutions. Including research experiences in the undergraduate classroom has been shown to positively impact students’ academic performance, development of skills, knowledge retention, and completion of STEM degrees. Via a collaborative effort between two institutions, Baylor College of Medicine (BCM) and University of St Thomas (UST), we designed and implemented a one-semester guided-research undergraduate laboratory course in which students modified a chromoprotein TinselPurple using directed mutagenesis. Our cohort includes two lab sections, that included 27 undergraduate students in total. The first two lab sessions of the semester were used to review lab safety, describe the project to the students, and to reinforce proper pipetting technique. This was followed by two rounds of directed evolution, in which students mutagenized TinselPurple gene fragments, reassembled the gene using a Golden Gate reaction, transformed bacteria and then screened colonies for brighter or altered pigmentation. The TinselPurple gene from the screened clones was sequenced and mutations were mapped to the gene and AlphaFold 3D structure. Student knowledge of the project and the methods was assessed using pre- and post-test that included multiple-choice and open answer questions. The post-test included an appreciation of science questionnaire in which students self-reported how they felt regarding various prompts. Additionally, students were assessed on their practical pipetting skills at the beginning and end of the lab course. Our findings indicate that students: (i) identified specific mutations that contributed to increased color intensity and hue variation, (ii) significantly improved their theoretical understanding of the project and the methods, (iii) increased their pipetting accuracy, and (iv) improved overall appreciation of the scientific process. Last, we observed that the collaborative experience facilitated student exposure to a professional research environment and emboldened students to continue their research at either BCM or UST under the guidance of experienced scientists.

Keywords: Genetics laboratory, guided research, directed evolution, course-based undergraduate research experience, chromoprotein, TinselPurple.