The multiple solvent crystal structures (MSCS) method uses organic solvents to map the surfaces of proteins. It identifies binding sites and allows for a more thorough examination of protein plasticity and hydration than could be achieved by a single structure. The crystal structures of bovine pancreatic ribonuclease A (RNAse A) soaked in the following organic solvents are presented: 50% dioxane, 50% dimethylformamide, 70% dimethylsulfoxide, 70% 1,6-hexanediol, 70% isopropanol, 50% R,S,R-bisfuran alcohol, 70% t-butanol, 50% trifluoroethanol, or 1.0M trimethylamine-N-oxide. This set of structures is compared with four sets of crystal structures of RNAse A from the protein data bank (PDB) and with the solution NMR structure to assess the validity of previously untested assumptions associated with MSCS analysis. Plasticity from MSCS is the same as from PDB structures obtained in the same crystal form and deviates only at crystal contacts when compared to structures from a diverse set of crystal environments. Furthermore, there is a good correlation between plasticity as observed by MSCS and the dynamic regions seen by NMR. Conserved water binding sites are identified by MSCS to be those that are conserved in the sets of structures taken from the PDB. Comparison of the MSCS structures with inhibitor-bound crystal structures of RNAse A reveals that the organic solvent molecules identify key interactions made by inhibitor molecules, highlighting ligand binding hot-spots in the active site. The present work firmly establishes the relevance of information obtained by MSCS.

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The mission of the Virginia Commonwealth University Louis Stokes Alliance for Minority Participation (VCU LSAMP) program is to increase the retention and graduation rates of students from underrepresented racial and ethnic groups in science, technology, engineering, and mathematics (STEM) majors and those who matriculate into graduate programs. VCU LSAMP offers a hybrid summer transition program (HSTP) focused on facilitating the high school to college and two-year to four-year college transition process for students majoring in STEM disciplines. The goals of the program are to 1) build community among a cohort of students, 2) orient students to VCU, 3) prepare students for the academic rigors of their first year in a STEM discipline at VCU, 4) expose students to opportunities and careers in STEM, 5) engage them in the VCU LSAMP program, and 6) provide financial support. Five distinct components of the VCU HSTP are 1) a six-week online summer component, 2) a 1 week on-campus orientation, 3) a Design Project Challenge, 4) a transfer student track, and 5) an academic year component. Evaluation data reveals that the HSTP assisted participants with adjustment to the college schedule and setting, facilitated the formation of study groups, and increased overall motivation to graduate. The online courses helped familiarize students with both the academic topics in their chemistry and mathematics classes and the behaviors and norms of STEM majors. On average, participants in the HSTP had higher retention (85%) and graduation (73%) rates when compared with their peers (81% and 64%, respectively). Furthermore, those students who complete the online classes’ requirements had a higher probability of receiving a grade of B or better in their first mathematics or chemistry class.

Rationale: Natural plant products have been used to promote health, prevent sickness, and treat various ailments. These products often consist of leaves, flowers, bark, roots, seeds, and/or other parts of the plant. Many of the pharmacologically active constituents of these products are known, but the pharmacology of these constituents may not be fully elucidated. Natural plant-based products are also available in various forms other than the raw plant material. A wide array of commercial products such as capsules, powders, extracts, and electronic cigarette (e-cigarette) electronic liquids (e-liquids) are readily available and can be purchased from various outlets, both store-based retailers and online. Newer e-cigarettes are often advertised as "heat not burn" and are used for "vaping" various forms of extracts including "waxes" and "dabs" and raw plant material.Methods: A single manufacturer was found online selling "24 different herbs" in powders, extracts, or e-liquids. These were advertised as "legal in the USA" and each product listed multiple effects. Eight e-liquids, six extracts (resins), and four powders from eight different "herbs," namely African dream, areca nut, blue lotus, damiana, kra thum na, kra thum kok, klip dagga, and wild lettuce, were purchased. An advertisement for these products stated, "Most people use the leaves, powder or resin in vaporizers." Direct analysis in real time AccuTOF™ mass spectrometry (DART-MS) was used to identify the psychoactive components in the natural products. Results:The psychoactive compounds that were identified in only two of the eight e-liquids, three of the five resins, and three of the four powders were arecaidine, arecoline, coumarin, entadamide, mitragynine, 7-hydroxymitragynine, and nuciferine. Conclusions:Psychoactive and potentially harmful substances were present in the powders and resins of the natural products. The newer types of e-cigarettes made for consuming natural products may increase their abuse potential.

The multiple-solvent crystal structure (MSCS) approach uses high concentrations of organic solvents to characterize the interactions and effects of solvents on proteins. Here, the method has been further developed and an MSCS data-handling pipeline is presented that uses the Detection of Related Solvent Positions (DRoP) program to improve data quality. DRoP is used to selectively model conserved water molecules, so that an advanced stage of structural refinement is reached quickly. This allows the placement of organic molecules more accurately and convergence on high-quality maps and structures. This pipeline was applied to the chromatin-associated protein barrier-to-autointegration factor (BAF), resulting in structural models with better than average statistics. DRoP and Phenix Structure Comparison were used to characterize the data sets and to identify a binding site that overlaps with the interaction site of BAF with emerin. The conserved water-mediated networks identified by DRoP suggested a mechanism by which water molecules are used to drive the binding of DNA. Normalized and differential B-factor analysis is shown to be a valuable tool to characterize the effects of specific solvents on defined regions of BAF. Specific solvents are identified that cause stabilization of functionally important regions of the protein. This work presents tools and a standardized approach for the analysis and comprehension of MSCS data sets.