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For a decade, BioMolViz has been developing tools to improve visual literacy instruction. In collaboration with the biochemistry and molecular biology (BMB) education community, our group authored a Biomolecular Visualization Framework to assess visual literacy skills and used the framework’s learning objectives in the backward design of assessments. Our validation process, which includes iterative revision by our working group of faculty, expert panel review, and large-scale classroom testing, has produced a subset of validated assessments which are available in our online repository, the BioMolViz Library. Nearly 200 assessments are now moving through the earlier phases of our validation process. With an eye always on inclusivity, we used our large-scale field testing data to examine performance trends. Upon observing some differences in performance that correlated with gender and race, we organized semi-structured interviews with small groups of undergraduate students to further evaluate our assessments. Disaggregating students into groups by gender, we asked students to share initial impressions and engage in collaborative reflection on their problem solving strategies. As we thematically code our interview transcripts, which include male and female groups from three U.S.-based institutions, we seek to further improve the clarity of our assessments, while exploring approaches to problem solving that may uncover demographic-related differences and make visual literacy more inclusive for all learners. 

Physical forces have a profound effect on growth, morphology, locomotion, and survival of organisms. At the level of individual cells, the role of mechanical forces is well recognized in eukaryotic physiology, but much less is known about prokaryotic organisms. Recent findings suggest an effect of physical forces on bacterial shape, cell division, motility, virulence, and biofilm initiation, but it remains unclear how mechanical forces applied to a bacterium are translated at the molecular level. In Gram-negative bacteria, multicomponent protein complexes can form rigid links across the cell envelope and are therefore subject to physical forces experienced by the cell. Here we manipulate tensile and shear mechanical stress in the bacterial cell envelope and use single-molecule tracking to show that octahedral shear (but not hydrostatic) stress within the cell envelope promotes disassembly of the tripartite efflux complex CusCBA, a system used by Escherichia coli to resist copper and silver toxicity. By promoting disassembly of this protein complex, mechanical forces within the cell envelope make the bacteria more susceptible to metal toxicity. These findings demonstrate that mechanical forces can inhibit the function of cell envelope protein assemblies in bacteria and suggest the possibility that other multicomponent, transenvelope efflux complexes may be sensitive to mechanical forces including complexes involved in antibiotic resistance, cell division, and translocation of outer membrane components. By modulating the function of proteins within the cell envelope, mechanical stress has the potential to regulate multiple processes required for bacterial survival and growth.