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1.
J R Soc Interface ; 21(214): 20230732, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38774958

RESUMO

The concept of an autocatalytic network of reactions that can form and persist, starting from just an available food source, has been formalized by the notion of a reflexively autocatalytic and food-generated (RAF) set. The theory and algorithmic results concerning RAFs have been applied to a range of settings, from metabolic questions arising at the origin of life, to ecological networks, and cognitive models in cultural evolution. In this article, we present new structural and algorithmic results concerning RAF sets, by studying more complex modes of catalysis that allow certain reactions to require multiple catalysts (or to not require catalysis at all), and discuss the differing ways catalysis has been viewed in the literature. We also focus on the structure and analysis of minimal RAFs and derive structural results and polynomial-time algorithms. We then apply these new methods to a large metabolic network to gain insights into possible biochemical scenarios near the origin of life.


Assuntos
Algoritmos , Catálise , Modelos Biológicos , Bioquímica , Origem da Vida
2.
Methods Enzymol ; 696: 109-154, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38658077

RESUMO

The use of molecular dynamics (MD) simulations to study biomolecular systems has proven reliable in elucidating atomic-level details of structure and function. In this chapter, MD simulations were used to uncover new insights into two phylogenetically unrelated bacterial fluoride (F-) exporters: the CLCF F-/H+ antiporter and the Fluc F- channel. The CLCF antiporter, a member of the broader CLC family, has previously revealed unique stoichiometry, anion-coordinating residues, and the absence of an internal glutamate crucial for proton import in the CLCs. Through MD simulations enhanced with umbrella sampling, we provide insights into the energetics and mechanism of the CLCF transport process, including its selectivity for F- over HF. In contrast, the Fluc F- channel presents a novel architecture as a dual topology dimer, featuring two pores for F- export and a central non-transported sodium ion. Using computational electrophysiology, we simulate the electrochemical gradient necessary for F- export in Fluc and reveal details about the coordination and hydration of both F- and the central sodium ion. The procedures described here delineate the specifics of these advanced techniques and can also be adapted to investigate other membrane protein systems.


Assuntos
Bioquímica , Biologia Computacional , Fluoretos , Simulação de Dinâmica Molecular , Fluoretos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Transporte de Íons/fisiologia , Canais de Cloreto/química , Canais de Cloreto/metabolismo , Eletrofisiologia , Bioquímica/métodos , Biologia Computacional/métodos , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Transporte Biológico Ativo/fisiologia
3.
CBE Life Sci Educ ; 23(2): ar16, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38620007

RESUMO

Interpreting three-dimensional models of biological macromolecules is a key skill in biochemistry, closely tied to students' visuospatial abilities. As students interact with these models and explain biochemical concepts, they often use gesture to complement verbal descriptions. Here, we utilize an embodied cognition-based approach to characterize undergraduate students' gesture production as they described and interpreted an augmented reality (AR) model of potassium channel structure and function. Our analysis uncovered two emergent patterns of gesture production employed by students, as well as common sets of gestures linked across categories of biochemistry content. Additionally, we present three cases that highlight changes in gesture production following interaction with a 3D AR visualization. Together, these observations highlight the importance of attending to gesture in learner-centered pedagogies in undergraduate biochemistry education.


Assuntos
Gestos , Estudantes , Humanos , Bioquímica/educação
5.
Nurse Educ Today ; 138: 106188, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38554567

RESUMO

BACKGROUND: Many nursing students struggle with the disciplines of biosciences, particularly Anatomy, physiology, and biochemistry, which are introduced in the first year. Nursing students' motivation, prior knowledge, and academic performance matter, but teaching methods may also influence students' learning process. Retrieving knowledge through testing has previously proven to enhance learning to a greater extent than time spent on other classroom activities. OBJECTIVE: The aim of this study was to explore nursing students' experiences with test-enhanced learning as a way of enhancing learning in Anatomy, physiology, and biochemistry. DESIGN: The lectures in each topic were followed by testing five days later. The tests were typically multiple-choice tests with short reply-times. The effect was measured in terms of students' self-reported level of satisfaction with test-enhanced learning, and their performance on the final exam in Anatomy, physiology, and biochemistry. The tests were performed in teams to avoid stressful situations that could negatively affect the students' learning process. RESULTS: A key achievement from introducing test-enhanced learning in the Anatomy, physiology, and biochemistry course was a perceived higher learning outcome and increased engagement and motivation among the students, resulting in resulting in more students achieving the highest grades (A and B). However, the students' academic results from upper secondary school also seemed to matter for their achievements on the final exam. CONCLUSION: These results indicated that many students benefited from test-enhanced learning, suggesting that test-enhanced learning can be an important teaching strategy in nursing education, particularly for biosciences.


Assuntos
Bacharelado em Enfermagem , Avaliação Educacional , Aprendizagem , Estudantes de Enfermagem , Humanos , Estudantes de Enfermagem/psicologia , Estudantes de Enfermagem/estatística & dados numéricos , Estudos Transversais , Avaliação Educacional/métodos , Bacharelado em Enfermagem/métodos , Feminino , Masculino , Motivação , Anatomia/educação , Bioquímica/educação , Adulto Jovem , Fisiologia/educação , Adulto
6.
J Biol Chem ; 300(4): 107131, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38432634

RESUMO

Many interactions involving a ligand and its molecular target are studied by rapid kinetics using a stopped-flow apparatus. Information obtained from these studies is often limited to a single, saturable relaxation that is insufficient to resolve all independent rate constants even for a two-step mechanism of binding obeying induced fit (IF) or conformational selection (CS). We introduce a simple method of general applicability where this limitation is overcome. The method accurately reproduces the rate constants for ligand binding to the serine protease thrombin determined independently from the analysis of multiple relaxations. Application to the inactive zymogen precursor of thrombin, prethrombin-2, resolves all rate constants for a binding mechanism of IF or CS from a single, saturable relaxation. Comparison with thrombin shows that the prethrombin-2 to thrombin conversion enhances ligand binding to the active site not by improving accessibility through the value of kon but by reducing the rate of dissociation koff. The conclusion holds regardless of whether binding is interpreted in terms of IF or CS and has general relevance for the mechanism of zymogen activation of serine proteases. The method also provides a simple test of the validity of IF and CS and indicates when more complex mechanisms of binding should be considered.


Assuntos
Bioquímica , Cinética , Ligantes , Precursores Enzimáticos/metabolismo , Precursores Enzimáticos/química , Ligação Proteica , Conformação Proteica , Protrombina/metabolismo , Protrombina/química , Trombina/metabolismo , Trombina/química , Bioquímica/métodos , Serina Proteases/metabolismo , Domínio Catalítico
8.
Int J Mol Sci ; 25(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38396673

RESUMO

Analytical mass spectrometry applies irreplaceable mass spectrometric (MS) methods to analytical chemistry and chemical analysis, among other areas of analytical science [...].


Assuntos
Bioquímica , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas/métodos
10.
Biochem Mol Biol Educ ; 52(3): 317-322, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38308530

RESUMO

As a strategy to carry out a better achievement in the Biochemistry course, undergraduate dentistry education manage a traditional course on the basic concepts of general chemistry necessary in the understanding of Biochemistry. In order to evaluate the effectiveness of learning outcome, we aimed to develop an evaluation tool that was applied to first-year dental students before and after receiving the general chemistry classes. Randomized trial consisted of 50 items distributed in 10 categories. The evaluation was applied to the students who took the Oral Biology course in the periods comprising 2020, 2021, and 2022 to a population of 109 students. Our results showed that after receiving the course the improvement rate was 20.71% with significant differences in each category. In conclusion, the introductory course allows students coming from different school systems to attend Biochemistry with similar knowledge of general chemistry.


Assuntos
Bioquímica , Currículo , Educação em Odontologia , Avaliação Educacional , Estudantes de Odontologia , Humanos , Bioquímica/educação , Educação em Odontologia/métodos , Aprendizagem
11.
Biochem Mol Biol Educ ; 52(3): 340-347, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38358340

RESUMO

The ability to connect key concepts of biochemistry with clinical presentations is essential for the development of clinical reasoning skills and adaptive expertise in medical trainees. To support the integration of foundational and clinical sciences in our undergraduate health science curricula, we developed a small group active learning exercise during which interprofessional groups of students use clinical cases to explore the biochemistry, diagnostic strategy, and evidence-based treatment options of inborn errors of metabolism (IEM). We designed multistage learning modules consisting of (1.) low-fidelity case simulations of pediatric patients presenting with IEMs, (2.) guided group discussions on clinical biochemistry, differential diagnoses, and diagnostic strategies, (3.) oral presentations of clinical reasoning strategies, and (4.) discussion of relevant evidence-based medicine topics related to the cases. These modules Scientific Knowledge Integrated in Patient Presentations (SKIPPs) were added to a first-semester foundational sciences course serving five health professions programs. The assessment of learning outcomes by students and faculty shows that SKIPPs sessions are well-received activities that significantly improve trainees' ability to integrate foundational science concepts into clinical scenarios, to practice interprofessional teamwork and to develop clinical reasoning skills.


Assuntos
Bioquímica , Currículo , Educação de Graduação em Medicina , Aprendizagem Baseada em Problemas , Humanos , Bioquímica/educação , Aprendizagem Baseada em Problemas/métodos , Estudantes de Medicina
12.
Biochem Mol Biol Educ ; 52(3): 348-358, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38400827

RESUMO

Enzymes are nature's catalysts, mediating chemical processes in living systems. The study of enzyme function and mechanism includes defining the maximum catalytic rate and affinity for substrate/s (among other factors), referred to as enzyme kinetics. Enzyme kinetics is a staple of biochemistry curricula and other disciplines, from molecular and cellular biology to pharmacology. However, because enzyme kinetics involves concepts rarely employed in other areas of biology, it can be challenging for students and researchers. Traditional graphical analysis was replaced by computational analysis, requiring another skill not core to many life sciences curricula. Computational analysis can be time-consuming and difficult in free software (e.g., R) or require costly software (e.g., GraphPad Prism). We present Enzyme Kinetics Analysis (EKA), a web-tool to augment teaching and learning and streamline EKA. EKA is an interactive and free tool for analyzing enzyme kinetic data and improving student learning through simulation, built using R and RStudio's ShinyApps. EKA provides kinetic models (Michaelis-Menten, Hill, simple reversible inhibition models, ternary-complex, and ping-pong) for users to fit experimental data, providing graphical results and statistics. Additionally, EKA enables users to input parameters and create data and graphs, to visualize changes to parameters (e.g., K M or number of measurements). This function is designed for students learning kinetics but also for researchers to design experiments. EKA (enzyme-kinetics.shinyapps.io/enzkinet_webpage/) provides a simple, interactive interface for teachers, students, and researchers to explore enzyme kinetics. It gives researchers the ability to design experiments and analyze data without specific software requirements.


Assuntos
Enzimas , Software , Cinética , Enzimas/metabolismo , Humanos , Bioquímica/educação , Internet , Estudantes , Ensino , Currículo
13.
Exp Oncol ; 45(4): 537-538, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38328834

RESUMO

With deep sadness, we announce that on December 10, 2023, at the age of 86 passed away an outstanding Ukrainian scientist in the field of oncology, analytical enzymology, and pharmacology, a Laureate of the State Prize of Ukraine for Science and Technology, a member of the Federation of European Biochemical Societies, a member of the State Expert Center of the Ministry of Health of Ukraine, Doctor of Medical Sciences, Professor Volodymyr Oleksiyovych SHLYAKHOVENKO.


Assuntos
Bioquímica , Oncologia , Bioquímica/história , Ucrânia
14.
Biochem Mol Biol Educ ; 52(2): 249-251, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38319132

RESUMO

Innovations in medical education, including the integration of narrative-based tales, are transforming the way complex biochemical concepts are taught and understood. In this "Idea to Explore", the essence of integrating tales that personify molecules and depict biochemical processes as engaging stories to enhance student engagement, promote active learning, and improve knowledge retention is discussed. It also explores the effectiveness of scientific discovery games and traditional scientific stories in deepening students' interest in biochemistry. Highlighting the potential of narrative methods to make biochemistry more accessible and engaging, educators are encouraged to adopt creative teaching tools that promote critical thinking, problem-solving, and communication skills, thereby inspiring active participation, and lifelong learning in biochemistry.


Assuntos
Educação Médica , Estudantes de Medicina , Humanos , Aprendizagem Baseada em Problemas , Pensamento , Bioquímica/educação
15.
Nucleic Acids Res ; 52(5): 2130-2141, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38407292

RESUMO

Outliers in scientific observations are often ignored and mostly remain unreported. However, presenting them is always beneficial since they could reflect the actual anomalies that might open new avenues. Here, we describe two examples of the above that came out of the laboratories of two of the pioneers of nucleic acid research in the area of protein biosynthesis, Paul Berg and Donald Crothers. Their work on the identification of D-aminoacyl-tRNA deacylase (DTD) and 'Discriminator hypothesis', respectively, were hugely ahead of their time and were partly against the general paradigm at that time. In both of the above works, the smallest and the only achiral amino acid turned out to be an outlier as DTD can act weakly on glycine charged tRNAs with a unique discriminator base of 'Uracil'. This peculiar nature of glycine remained an enigma for nearly half a century. With a load of available information on the subject by the turn of the century, our work on 'chiral proofreading' mechanisms during protein biosynthesis serendipitously led us to revisit these findings. Here, we describe how we uncovered an unexpected connection between them that has implications for evolution of different eukaryotic life forms.


Assuntos
Aminoaciltransferases , Eucariotos , Glicina , Biossíntese de Proteínas , Aminoácidos/genética , Aminoaciltransferases/genética , Glicina/genética , Aminoacil-RNA de Transferência/metabolismo , Pesquisa , Bioquímica , Eucariotos/química , Eucariotos/genética
16.
J Biol Chem ; 300(2): 105625, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38185246

RESUMO

This Reflection article begins with my family background and traces my career through elementary and high school, followed by time at the University of Illinois, Vanderbilt University, the University of Michigan, and then for 98 semesters as a Vanderbilt University faculty member. My research career has dealt with aspects of cytochrome P450 enzymes, and the basic biochemistry has had applications in fields as diverse as drug metabolism, toxicology, medicinal chemistry, pharmacogenetics, biological engineering, and bioremediation. I am grateful for the opportunity to work with the Journal of Biological Chemistry not only as an author but also for 34 years as an Editorial Board Member, Associate Editor, Deputy Editor, and interim Editor-in-Chief. Thanks are extended to my family and my mentors, particularly Profs. Harry Broquist and Minor J. Coon, and the more than 170 people who have trained with me. I have never lost the enthusiasm for research that I learned in the summer of 1968 with Harry Broquist, and I have tried to instill this in the many trainees I have worked with. A sentence I use on closing slides is "It's not just a laboratory-it's a fraternity."


Assuntos
Bioquímica , Sistema Enzimático do Citocromo P-450 , Humanos , Docentes , Mentores , Universidades , Ensino
17.
Biochem Mol Biol Educ ; 52(3): 311-316, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38193602

RESUMO

A literature review is an important part of conducting academic research. Knowing how to conduct a literature search and write a high-quality literature review is a valuable skill. Herein, the authors describe the method of introducing a literature review writing exercise in an upper-level biochemistry course. Since 2020, authors have collaborated with numerous undergraduates writing literature reviews on topics in biochemistry that resulted in peer-reviewed publications. Authors believe that this unique idea of providing a course-based undergraduate research experience (CURE) to many undergraduates, especially those who otherwise do not receive collaborative research experience through traditional research paths, must be shared with other instructors.


Assuntos
Bioquímica , Currículo , Estudantes , Redação , Bioquímica/educação , Humanos , Universidades , Literatura de Revisão como Assunto
18.
Biochem Mol Biol Educ ; 52(2): 220-227, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38226712

RESUMO

Electron transport chain and oxidative phosphorylation are always a challenging topic for students studying metabolism. We had adopted blended learning in metabolism teaching and evaluated the learning experiences of students. In this project, a pre-class learning aid the Story Mode and a post-class learning aid the Revision Mode in the Powerland was developed that facilitated students learning electron transport chain and oxidative phosphorylation. In the Story Mode, pathways were presented by short animations and simplified diagram that allowed students to understand basic concepts and recall simple facts of the topic. Students were asked to watch the animations before class to acquire lower level of cognitive learning first, and this facilitated students in understanding more complicated concepts later on during class. Another challenge that students faced was that they were especially weak at integrating metabolic pathways and understand the relationships between these pathways. A metro map was designed in the Revision Mode that aided students in knowledge integration, and the functions of biomolecules were summarized in flashcards that helped students in revising the concepts. This interactive self-learning tool was packaged as a courseware using the Articulate Storyline.


Assuntos
Aprendizagem , Fosforilação Oxidativa , Humanos , Transporte de Elétrons , Bioquímica/educação , Estudantes
19.
Nat Chem ; 16(2): 249-258, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37857844

RESUMO

Nucleoside diphosphates and triphosphates impact nearly every aspect of biochemistry; however, the use of such compounds as tools or medicinal leads for nucleotide-dependent enzymes and receptors is hampered by their rapid in vivo metabolism. Although a successful strategy to address the instability of the monophosphate moiety in oligonucleotide therapeutics has been accomplished by their isosteric replacement with phosphorothioates, no practical methods exist to rapidly and controllably access stereopure di- and triphosphate thioisosteres of both natural and unnatural nucleosides. Here we show how a modular, reagent-based platform can enable the stereocontrolled and scalable synthesis of a library of such molecules. This operationally simple approach provides access to pure stereoisomers of nucleoside α-thiodiphosphates and α-thiotriphosphates, as well as symmetrical or unsymmetrical dinucleoside thiodiphosphates and thiotriphosphates (including RNA cap reagents). We demonstrate that ligand-receptor interactions can be dramatically influenced by P-stereochemistry, showing that such thioisosteric replacements can have profound effects on the potency and stability of lead candidates.


Assuntos
Nucleosídeos , Nucleotídeos , Nucleosídeos/química , Nucleotídeos/química , Polifosfatos , Bioquímica
20.
Biochem Mol Biol Educ ; 52(1): 58-69, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37815098

RESUMO

We present as a case study the evolution of a series of participant-centered workshops designed to meet a need in the life sciences education community-the incorporation of best practices in the assessment of student learning. Initially, the ICABL (Inclusive Community for the Assessment of Biochemistry and Molecular Biology/BMB Learning) project arose from a grass-roots effort to develop material for a national exam in biochemistry and molecular biology. ICABL has since evolved into a community of practice in which participants themselves-through extensive peer review and reflection-become integral stakeholders in the workshops. To examine this evolution, this case study begins with a pilot workshop supported by seed funding and thoughtful programmatic assessment, the results of which informed evidence-based changes that, in turn, led to an improved experience for the community. Using participant response data, the case study also reveals critical features for successful workshops, including participant-centered activities and the value of frequent peer review of participants' products. Furthermore, we outline a train-the-trainer model for creating a self-renewing community by bringing new perspectives and voices into an existing core leadership team. This case study, then, offers a blueprint for building a thriving, evolving community of practice that not only serves the needs of individual scientist-educators as they seek to enhance student learning, but also provides a pathway for elevating members to positions of leadership.


Assuntos
Médicos , Estudantes , Humanos , Bioquímica/educação , Biologia Molecular/educação , Aprendizagem
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