Course-based undergraduate research experiences (CUREs) are laboratory courses that integrate broadly relevant problems, discovery, use of the scientific process, collaboration, and iteration to ...provide more students with research experiences than is possible in individually mentored faculty laboratories. Members of the national Malate dehydrogenase CUREs Community (MCC) investigated the differences in student impacts between traditional laboratory courses (control), a short module CURE within traditional laboratory courses (mCURE), and CUREs lasting the entire course (cCURE). The sample included approximately 1,500 students taught by 22 faculty at 19 institutions. We investigated course structures for elements of a CURE and student outcomes including student knowledge, student learning, student attitudes, interest in future research, overall experience, future GPA, and retention in STEM. We also disaggregated the data to investigate whether underrepresented minority (URM) outcomes were different from White and Asian students. We found that the less time students spent in the CURE the less the course was reported to contain experiences indicative of a CURE. The cCURE imparted the largest impacts for experimental design, career interests, and plans to conduct future research, while the remaining outcomes were similar between the three conditions. The mCURE student outcomes were similar to control courses for most outcomes measured in this study. However, for experimental design, the mCURE was not significantly different than either the control or cCURE. Comparing URM and White/Asian student outcomes indicated no difference for condition, except for interest in future research. Notably, the URM students in the mCURE condition had significantly higher interest in conducting research in the future than White/Asian students.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract only
Academic integrity can be defined in many ways and can have different implications and applications from both the student and instructor perspective. Following a pilot study gathering ...data from the authors’ host institutions, data was gathered from faculty attending the summer 2019 ASBMB Transforming Education meeting during a “living poster” presentation on the topic. Specifically, the authors asked questions probing faculty knowledge about cultural norms at their institution surrounding academic integrity and what they perceived were their biggest challenges in the classroom. Faculty responses focused on understanding motivations for student cheating, sharing real‐world examples of unethical behavior with students, and determining strategies for mitigating cheating. These observations led to the development of a survey distributed across the STEM community, from which the data will be used to generate a reference of best practices for fostering academic integrity in the science classroom.
Chemicals used extensively and intensively in our technological society are currently predicted to have surpassed the 100,000 mark in numbers and depending on their properties, modes, and quantity of ...use, a large number of these chemicals can reach the environment and have unpredictable but potentially harmful environmental and health impacts. Accurate methods of monitoring the levels of these chemicals, an understanding of their potential to damage natural inhabitants to these waters, and the ability to properly develop a risk assessment strategy are all critical pieces to the maintenance of a healthy aquatic ecosystem that does not pose a threat to human safety. Current research has identified several emerging contaminants in Lake Erie beach waters of Presque Isle State Park, including fluoxetine, triclosan, estradiol, and diuron, as well as the artificial sweetener sucralose. All of these chemicals have been shown to have negative health consequences in organisms from bacteria to humans. For most of these, the levels in the Park approach or exceed levels known to cause harm to aquatic species. We have also investigated the ability of these chemicals of concern to have genotoxic (and often synergistic) effects.
Abstract only
Constructivist learning theory, as formalized by Piaget, suggests that learners construct new knowledge from their experiences and is best facilitated with pedagogic approaches that ...promote learning by doing. A traditional stumbling block in undergraduate biochemistry is the structure‐function relationship in proteins. Students often first encounter this relationship in the study of the oxygen‐binding proteins hemoglobin and myoglobin. While the molecular structures and physiological roles of these proteins are known in detail, the interplay of additional components (e.g. carbonic anhydrase, O
2
/CO
2
levels, 2,3‐BPG) can make this dance in the circulatory system a challenge for students to master conceptually. In this study, an active learning approach through a hands‐on game was used to facilitate student mastery, whereby students become the molecules responsible for oxygen transport in the circulatory system. By students having a greater understanding of how this system works properly in a healthy state, they can better understand aspects that result in disease (e.g. Sickle‐cell anemia and hemoglobin variants) or predict outcomes arising from changes in environmental conditions (e.g. high altitude or hyperventilation). The objective of this study is to determine if there is any difference between perceived and actual success in learning outcomes as students partake in this alternative pedagogical approach. The working hypothesis is that utilization of constructivist pedagogies, such as an active learning game, will result in higher perceived and actual student success. Data is being collected during the Fall 2015 semester to evaluate this hypothesis.
Systematic evolution of ligands by exponential enrichment (SELEX) is a methodology in biochemistry for identifying nucleic acid sequences capable of adopting a shape that binds a target molecule. The ...process involves several rounds of the polymerase chain reaction (PCR) to amplify DNA sequences followed by steps that ultimately separate and enrich the population of DNAs with sequences having a high affinity for the target molecule. Four main reagents required for any PCR reaction include: 1 ‐ DNA template, 2 ‐ DNA primers, 3 ‐ dNTPs, and 4 ‐ DNA polymerase. PCR optimization is frequently performed to identify experimental conditions that are optimal for the chosen template and primers. This can be a costly step of the experimental procedures, as commercially available DNA polymerases can range from a few hundred to thousands of dollars. We have undertaken the process of overexpressing and purifying the heat‐stable DNA polymerase from Thermus aquaticus. A plasmid containing the gene for Taq DNA polymerase was transformed to BL21(DE3) E. coli cells. Cell cultures of these transformed cells can then be grown to saturation at 37°C and overexpression initiated with the addition of IPTG. The desired Taq polymerase will be purified from a portion of the cleared lysate using ion‐exchange chromatography. PCR activity using a standard template and primers can then be evaluated using samples of purified and unpurified Taq polymerase with comparison to several commercial samples.
Using CUREs to integrate research into the teaching environment has significant impact on motivation and persistence of STEM students as seen from traditional undergraduate research experiences. ...Specifically, involvement in undergraduate research provides opportunities to think and act as scientists, bolsters feelings of belonging, and improves confidence in STEM. THE MDH CURES Community is an NSF funded community of faculty using malate dehydrogenase (MDH) to engage students in CUREs. One of several themes of MDH CUREs is protein‐protein interactions and the impact of post‐translational modification. Here we present how several primarily undergraduate and comprehensive universities and a community college, several of which are Hispanic Serving Institutions (HSIs), have included MDH‐CS interactions in their classroom. Interactions between cytosolic MDH and four other proteins thought to share substrate/product were explored in silico at a community college in a first‐year chemistry course. At Malone university, students used MS phosphorylation information to predict potential interactions which they explored by mutagenesis. Students at Mercyhust University have used in‐silico and experimental methods to design and then test CS and MDH interactions using pull down assays. Students at Suffolk University created a novel bacterial two‐hybrid model to test interactions between cytosolic and mitochondrial MDH with CS in a genetics course. In a horizontally integrated sequence, students at University of San Diego modeled potential interactions between MDH and CS and the effects of various mutations. In a subsequent semester, students used that information to analyze the mutation’s functional impact and effect on interactions with MDH‐CS using a pull‐down assay. Each project is an ongoing effort working as part of the MCC network. Approaches and lessons learned will be shared.
Abstract only
Biosensors provide a unique platform for analyte detection, generating a dose‐dependent response through a binding‐specific conformational change. While most ligand‐binding biomolecules ...are not biosensing by default, many can be engineered to be so through the introduction of an alternative nonbinding (and thus nonsignaling) conformation. While this strategy has been met with limited success with proteins, the sequence‐structure‐function relationship inherent with oligonucleotides has led to the creation of structure‐switching aptamer‐based biosensors for many target ligands. G‐quartet sequences (GQS) generate a characteristic structural motif in the presence of potassium ions. While previous work has been done to engineer this motif into structure‐switching biosensors for potassium, no work has been done to edit their dynamic ranges. Here, we report the rational design of six sequences to bind potassium with different apparent binding affinities. We demonstrate a correlation between the experimentally determined binding affinity for potassium (via circular dichroism) and the theoretically determined free energy of the alternative structure (determined computationally by nearest‐neighbor parameters). This work demonstrates the ability to rationally design an aptamer‐based biosensor to operate in any desired range of analyte concentration weaker than the intrinsic binding constant.
•We report the rational design of structure-switching DNA aptamers for potassium.•The shift between non-binding and binding-competent states was determined experimentally.•The stability of the ...non-binding state was estimated computationally.•A linear free energy relationship between these values was established.
Structure-switching molecules provide a unique means for analyte detection, generating a response to analyte concentration through a binding-specific conformational change between non-binding and binding-competent states. While most ligand-binding molecules are not structure switching by default, many can be engineered to be so through the introduction of an alternative non-binding (and thus non-signalling) conformation. This population-shift mechanism is particularly effective with oligonucleotides and has led to the creation of structure-switching aptamers for many target ligands. Here, we report the rational design of structure-switching DNA aptamers, based on the thrombin binding aptamer (TBA), that bind potassium with affinities that bridge the gap between previously reported weak-binding and strong-binding aptamers. We also demonstrate a correlation between the free energy of the experimentally determined binding affinity for potassium and the computationally estimated free energy of the alternative (non-binding) structure.
Sucralose and many other non‐metabolizable food additives, drugs, and consumer personal care products are accumulating to detectable levels in our environment. Traditional analytical instrumentation ...or antibody‐based ELISA assays can quantitatively assess their presence and have been used to report detectable levels of sucralose in Lake Erie. Aptamers are DNA or RNA based molecules that adopt a specific structure that allows for a characteristic function, often the binding of a small molecule. Biosensors based on aptamer sequences thus provide a unique platform for detection of small molecules, generating a response to analyte through a binding‐specific conformational change. While aptamers have been developed for many target ligands, none exist for sucralose. SELEX (systematic evolution of ligands by exponential enrichment) is a methodology useful for selecting “winning” sequences ‐ the ability to adopt a shape that binds a target molecule ‐ from a library of possible sequences. The process involves several steps that ultimately separate and enrich the population of DNAs with sequences having a high affinity for sucralose. FLU‐MAG SELEX uses two specific modifications to traditional SELEX. Magnetic bead technology (“MAG”) will facilitate separation of mixtures of solutions while fluorescently labeled primers (“FLU”) will allow for the quantitative monitoring of DNAs as SELEX proceeds. Winning sequences can then be modified into structure‐switching biosensors capable of selective and sensitive detection of sucralose from environmental samples.
PDF
