Extending Students' Practice of Metacognitive Regulation Strategies in the Undergraduate Chemistry Laboratory and Investigation of Pb2+ Binding to Calmodulin with Circular Dichroism and Molecular Dynamics Modeling
The following dissertation was composed of two projects in chemistry education and benchwork/computational biochemistry. The chemistry education research explored students' practice of metacognitive strategies while solving open-ended laboratory problems when engaged in an instructional environment, the Science Writing Heuristic (SWH), that was characterized as supporting metacognitive regulation strategy use. Through in-depth interviews with students, results demonstrated that students in the SWH environment, compared to non-SWH students, used metacognitive strategies to a greater degree and to a greater depth when solving open-ended laboratory problems. As students engaged in higher levels of metacognitive regulation, their elective use of peers became a prominent path for supporting the practice of metacognitive strategies. Students claimed that the structure of the SWH weekly laboratory experiments improved their ability to solve open-ended lab problems. This research not only provided a lens into students' descriptions of their regulation strategy practices in the laboratory, but it also supported that the way that a laboratory environment is arranged can affect these regulation strategy practices and their transfer to new situations. In the biochemical study on the binding of Pb<super>2+<super> to calmodulin (CaM), data was acquired via circular dichroism (CD) and molecular dynamics modeling. CD signal data indicated a unique signal from Pb-CaM and a significantly smaller ratio θ208/θ222 for Pb-CaM than Ca-CaM. An analysis of secondary structure content indicated that α-helical structure decreased and random coil structure increased when CaM was saturated with Pb<super>2+<super> compared to Ca<super>2+<super> saturated CaM. A molecular dynamics simulation of Pb<super>2+<super> binding to CaM showed that Pb<super>2+<super> ions bound to sites outside of the known canonical binding sites including the linker region, and indicated change in secondary structure. These results support the theory of opportunistic binding of Pb<super>2+<super> to CaM, and confirm previous research of binding sites in the linker region (Met 76 to Asp 84). The method of random ion (Pb<super>2+<super>) placement with a protein (CaM) in a water box provided an accurate prediction of binding sites, correctly predicting four of five binding sites found on both crystal structures of Pb-CaM.
Calcium binding proteins, General Chemistry Laboratory, Lead Toxicity, Metacognitive Regulation Strategies, Protein Structure, Function, Dynamics, Science Writing Heurisitic, Science and Mathematics Education
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