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Many chemistry laboratory exercises follow a given protocol with known results. Such traditional laboratories rarely give students an accurate representation of how research is conducted, the scientific practices involved in research, and the ownership that accompanies developing and carrying out an independent project. Several laboratory reforms have sought to overcome these limitations, including the creation of course-based undergraduate research experiences (CUREs). The CURE design is meant to emulate authentic research in the teaching laboratory by having students perform novel experiments with unknown results. In this article, we describe our implementation of a CURE for an upper-level physical chemistry laboratory course. Our students carried out novel research using molecular dynamics simulations, isothermal titration calorimetry, and stopped-flow kinetics to study ligand binding to the protein human serum albumin. We studied the effects of the CURE laboratory redesign via a mixed-methods approach. We use the CURE Survey by Lopatto and colleagues to record students' perceived gains in course elements and benefits. We also conducted student interviews to gain an in-depth view of their experience with the CURE laboratory. Our findings suggest that implementing a CURE in an upper-level chemistry laboratory results in similar outcomes to other CURE experiences (which most often occur at the introductory level), can standardize undergraduate research training, and can increase student ownership of laboratory work. We conclude that developing CURE courses for upper-level chemistry courses is an effective way of enhancing undergraduate laboratory training and increasing student experience with research.

The substitutions of 2-aminopurine for adenine at six positions in the repeated [(CAG).sub.8] sequence that forms a stem-loop hairpin was used to assess the structural and thermodynamic properties of repeated trinucleotide sequences. The findings for the instability associated with repeated CAG hairpin which influenced the global secondary structure could be applied to interpret the structures adopted by other repeated (CAG) structures.

Proteinconformational heterogeneity and dynamics are known toplay an important role in enzyme catalysis, but their influence hasbeen difficult to observe directly. We have studied the effects ofheterogeneity in the catalytic reaction of pig heart lactate dehydrogenaseusing isotope edited infrared spectroscopy, laser-induced temperaturejump relaxation, and kinetic modeling. The isotope edited infraredspectrum reveals the presence of multiple reactive conformations ofpyruvate bound to the enzyme, with three major reactive populationshaving substrate C2 carbonyl stretches at 1686, 1679, and 1674 cm–1, respectively. The temperature jump relaxation measurementsand kinetic modeling indicate that these substates form a heterogeneousbranched reaction pathway, and each substate catalyzes the conversionof pyruvate to lactate with a different rate. Furthermore, the rateof hydride transfer is inversely correlated with the frequency ofthe C2 carbonyl stretch (the rate increases as the frequency decreases),consistent with the relationship between the frequency of this modeand the polarization of the bond, which determines its reactivitytoward hydride transfer. The enzyme does not appear to be optimizedto use the fastest pathway preferentially but rather accesses multiplepathways in a search process that often selects slower ones. Theseresults provide further support for a dynamic view of enzyme catalysiswhere the role of the enzyme is not just to bring reactants togetherbut also to guide the conformational search for chemically competentinteractions. [ABSTRACT FROM AUTHOR]