Molecular case studies (MCSs) are open educational resources that use a storytelling approach to engage students in biomolecular structure-function explorations, at the interface of biology and chemistry. Although MCSs are developed for a particular target audience with specific learning goals, they are suitable for implementation in multiple disciplinary course contexts. Detailed teaching notes included in the case study help instructors plan and prepare for their implementation in diverse contexts.
View Article and Find Full Text PDFThe COVID-19 pandemic emphasized the importance of peer communication networks for student outcomes. Herein, we describe the use of supplemental instructional videos created by former students and integrated into electronic lab notebooks, to restore the lost community-learning component using student voices in a de-densified upper-division biochemistry laboratory.
View Article and Find Full Text PDFUnderstanding the relationship between protein structure and function is a core-learning goal in biochemistry. Students often struggle to visualize proteins as three-dimensional objects that interact with other molecules to affect its biochemical consequences. We describe here a partial course-based undergraduate research experiences that has students exploring protein structure and function hands-on while authoring a molecular case study intended for others to use.
View Article and Find Full Text PDFIncreasing resistance against available orthosteric beta-lactamase inhibitors necessitates the search for novel and powerful inhibitor molecules. In this respect, allosteric inhibitors serve as attractive alternatives. Here, we examine the structural basis of inhibition in a hidden, druggable pocket in TEM-1 beta-lactamase.
View Article and Find Full Text PDFProgestins bind to the progestin receptor (PR) isoforms, PR-A and PR-B, in brain to influence development, female reproduction, anxiety, and stress. Hormone-activated PRs associate with multiple proteins to form functional complexes. In the present study, proteins from female mouse hypothalamus that associate with PR were isolated using affinity pull-down assays with glutathione S-transferase-tagged mouse PR-A and PR-B.
View Article and Find Full Text PDFDeclining efficiency of antibiotic-inhibitor combinatorial therapies in treating beta-lactamase mediated resistance necessitates novel inhibitor development. Allosteric inhibition offers an alternative to conventional drugs that target the conserved active site. Here, we show that the evolutionarily conserved PWP triad located at the N-terminus of the H10 helix directly interacts with the allosteric site in TEM-1 beta-lactamase and regulates its activity.
View Article and Find Full Text PDFThe laboratory setting is an exciting and gratifying place to teach because you can actively engage the students in the learning process through hands-on activities; it is a dynamic environment amenable to collaborative work, critical thinking, problem-solving and discovery. The guided inquiry-based approach described here guides the students through their laboratory work at a steady pace that encourages them to focus on quality observations, careful data collection and thought processes surrounding the chemistry involved. It motivates students to work in a collaborative manner with frequent opportunities for feedback, reflection, and modification of their ideas.
View Article and Find Full Text PDFMany in-vitro experiments performed to study the response of thiol-containing proteins to changes in environmental redox potentials use dithiothreitol (DTT) to maintain a preset redox environment throughout the experiments. However, the gradual oxidation of DTT during the course of the experiments, and the interaction between DTT and other components in the system, can significantly alter the initial redox potential and complicate data interpretation. Having an internal reporter of the actual redox potential of the assayed sample facilitates direct correlation of biochemical findings with experimental redox status.
View Article and Find Full Text PDFBackground: Notch receptors are normally cleaved during maturation by a furin-like protease at an extracellular site termed S1, creating a heterodimer of non-covalently associated subunits. The S1 site lies within a key negative regulatory region (NRR) of the receptor, which contains three highly conserved Lin12/Notch repeats and a heterodimerization domain (HD) that interact to prevent premature signaling in the absence of ligands. Because the role of S1 cleavage in Notch signaling remains unresolved, we investigated the effect of S1 cleavage on the structure, surface trafficking and ligand-mediated activation of human Notch1 and Notch2, as well as on ligand-independent activation of Notch1 by mutations found in human leukemia.
View Article and Find Full Text PDFVillin-type headpiece domains are compact motifs that have been used extensively as model systems for protein folding. Although the majority of headpiece domains bind actin, there are some that lack this activity. Here, we present the first NMR solution structure and (15)N-relaxation analysis of a villin-type headpiece domain natively devoid of F-actin binding activity, that of supervillin headpiece (SVHP).
View Article and Find Full Text PDFProteolytic resistance of Notch prior to ligand binding depends on the structural integrity of a negative regulatory region (NRR) of the receptor that immediately precedes the transmembrane segment. The NRR includes the 3 Lin12/Notch repeats and the juxtamembrane heterodimerization domain, the region of Notch1 most frequently mutated in T-cell acute lymphoblastic leukemia lymphoma (T-ALL). Here, we report the x-ray structure of the Notch1 NRR in its autoinhibited conformation.
View Article and Find Full Text PDFNotch receptors transmit signals between adjacent cells. Signaling is initiated when ligand binding induces metalloprotease cleavage of Notch within an extracellular negative regulatory region (NRR). We present here the X-ray structure of the human NOTCH2 NRR, which adopts an autoinhibited conformation.
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