Dr. Colin Smith Receives CAREER Grant from National Science Foundation (NSF)


Colin Smith, Professor of Chemistry

“Dynamics of Computationally Designed Fluorescent Proteins”

The goal of the research is to study and optimize the movement of microscopic, computationally designed proteins that use light to track the locations of biological molecules and reveal how living organisms work. While the structure of a protein is almost always necessary for function, it is often not sufficient. This project focuses on the critical but often neglected role of protein motion in enabling absorbance and reemission of light, a process known as fluorescence. We will first determine which protein shapes either enhance or inhibit fluorescence through detailed analysis of computer simulations and extensive experimental structural characterization. Second, we will test our models through redesign and experimental examination of brighter fluorescent protein variants. As part of these efforts, we will develop a general-purpose computer algorithm that enables rapid evaluation of how thousands of potential mutations affect the shape of the protein. Third, we will investigate the structural determinants of other important properties like the ability of the protein to prevent or facilitate switching fluorescence on and off. The ultimate aim of this project is to develop a detailed understanding of how these fluorescent proteins can be redesigned to make them truly useful tools for biological research. This will enable the creation of even more advanced versions of these and other protein machines (like enzymes) that can also help in the manufacture and recycling of materials at the chemical level.

 

 

Personick Wins Silver (and more) at USRowing Masters National Championships


Dr. Personick & teammates

From August 12-15th, Prof. Personick competed at the USRowing Masters National Championships on Melton Lake in Oak Ridge, Tennessee. The weather was hot, but the water was flat and cold—perfect for racing and keeping cool. Her team, Riverfront Recapture, won medals in 46 events – 24 gold, 11 silver and 11 bronze – a team record. After a fog delay each morning, Prof. Personick raced to win one silver medal (women’s open B four with coxswain*) and three bronze medals (women’s club A four with coxswain, mixed AA four with coxswain, and mixed B eight). She also finished fourth in the women’s open A four with coxswain and fifth in the women’s open A single sculls.

All of these finishes contributed points to Riverfront’s success in the team points competitions. The team won the men’s points trophy and finished second for club points, third for overall points (out of 112 teams), and second for the efficiency competition (points per athlete). Overall, it was a great success, and the team is now looking forward to the fall racing season!


Dr. Personick & teammates


Dr. Personick 


Medals & Hat


Dr. Personick’s team 


Melton Lake in Oak Ridge, Tennessee


Melton Lake in Oak Ridge, Tennessee

Results: https://herenow.com/results/#/races

Pictures: https://www.row2k.com/gallery/index.cfm?year=2021&category=Masters%20Nationals

* Letters indicate the average age of the crew: AA = 21-26, A = 27-35, B = 36-42

Dr. Benjamin Elling Joins the Chemistry Department

The Chemistry Department is delighted to welcome Dr. Benjamin Elling as an Assistant Professor of Chemistry. His recently renovated lab, in the space formerly occupied by Albert J. Fry, will investigate new methods to synthesize and reprocess polymers. This semester he will be teaching CHEM 373, an upper-level course on polymer chemistry.

Professor Elling received his BA in chemistry from Cornell University, where he synthesized polymers for anion exchange membranes in the lab of Geoff Coates. He then attended Stanford University, where he became the first PhD student of Yan Xia and developed methods for sequence-specific polymerization via the ring-opening metathesis of substituted cyclopropenes. Prior to his appointment at Wesleyan, Professor Elling was a postdoctoral scholar in the lab of Professor Will Dichtel, where he designed new covalent adaptable networks and investigated strategies for mixed plastic compatibilization.

Here at Wesleyan, Professor Elling will combine his interests in synthetic methods development and sustainability. His lab will focus on leveraging strain energy to create polymers capable of controlled degradation, reprocessing thermosets through novel exchange chemistries, and incorporating renewable building blocks such as carbon dioxide into materials. The Chemistry Department is very pleased to have him join us.

Dr. Suara Adediran Publishes Paper in Biochimica et Biophysica Acta (BBA) – Proteins and Proteomics

Dr. Adediran and co-authors Michael J. Morrison and R.F. Pratt have published a paper in Biochimica et Biophysica Acta (BBA) – Proteins and Proteomics. The title is “Detection of an Enzyme Isomechamism by Means of the Kinetics of Covalent Inhibition.”

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Abstract

Turnover of substrates by many enzymes involves free enzyme forms that differ from the stable form of the enzyme in the absence of substrate. These enzyme species, known as isoforms, have, in general, different physical and chemical properties than the native enzymes. They usually occur only in small concentrations under steady state turnover conditions and thus are difficult to detect. We show in this paper that in one particular case of an enzyme (a class C β-lactamase) with specific substrates (cephalosporins) the presence of an enzyme isoform (E′) can be detected by means of its different reactivity than the native enzyme (E) with a class of covalent inhibitors (phosphonate monoesters). Generation of E′ from E arises either directly from substrate turnover or by way of a branched path from an acyl-enzyme intermediate. The relatively slow spontaneous restoration of E from E′ is accelerated by certain small molecules in solution, for example cyclic amines such as imidazole and salts such as sodium chloride. Solvent deuterium kinetic isotope effects and the effect of methanol on cephalosporin turnover showed that for both E and E′, kcat is limited by deacylation of an acyl-enzyme intermediate rather than by enzyme isomerization.

The full text of the paper can be found at: https://www.sciencedirect.com/science/article/abs/pii/S157096392100087X

 

 

Dr. Colin Smith Receives NIH Grant

Colin Smith, Professor of Chemistry

The Smith Lab studies protein structure and dynamics using a combination of computer simulation and nuclear magnetic resonance (NMR) spectroscopy. They are particularly interested in optimizing the dynamics of computationally designed proteins and understanding how mutations allosterically affect the functions of natural proteins.

To advance the understanding of atomic-level mechanisms behind critical protein functions like enzyme catalysis and allosteric regulation, it is important to first elucidate a true representation of the protein in solution. In an effort to achieve this long term goal, Dr. Smith will use the recently developed Kinetic Ensemble approach to transform the way in which nuclear magnetic resonance (NMR) data is computationally modeled to solve protein structures and measure protein motions. NMR is one of the most powerful techniques for elucidating the structure and dynamics of proteins. It enables their study in solution (unlike X-ray crystallography) and can capture critical structural rearrangements as they happen at room temperature (unlike cryo-electron microscopy). However, despite these advantages, there have been relatively few practical improvements to one of the foundational aspects behind the way protein structures are solved, namely the calculation of interatomic distances from nuclear Overhauser effect (NOE) experiments. Such methods have remained largely qualitative, resulting in large uncertainties in the atomic positions for most NMR structures. Also, the field has almost completely ignored how angular motion and kinetics affect the NOE, resulting in atoms appearing much further away from one another than they actually are. To overcome these significant deficiencies, Dr. Smith and his team will implement and test new Kinetic Ensemble-based refinement algorithms that are considerably more accurate and physically realistic than previous approaches, accounting for both angular motion and kinetics. To eliminate a significant fraction of the systematic and random structural errors resulting from poorly quantified NMR spectra, they will also integrate advances made by the FitNMR peak quantification software recently developed by their lab. These methods will be used to create better experimental NMR structures, more exhaustive models of side chain dynamics, and determine differences between solution and crystal states with unprecedented detail. This work will allow much more accurate determination of the structural dynamics in parts of the protein exhibiting significant fluctuations, including protein active sites, regulatory regions, and hidden binding sites. Such knowledge will advance our fundamental understanding of protein biophysics and facilitate rational design of new therapeutics.

Funding for this R15 Grant is provided by National Institute of General Medical Sciences (NIGMS).

Dr. Brian Northrop Receives NSF Grant

Northrop’s proposal, titled “Phenazine chemistry as a means of assembling multifunctional π-conjugated organic materials” is motivated by the desire to understand how the structure, functionality, and dimensionality of π-conjugated organic materials impacts their physical, optical, redox, and electronic properties. Toward this fundamental goal he and his students will use the condensation reactions between ortho-phenylenediamine derivatives with ortho-quinone compounds to prepare multifunctional phenazine derivatives. Phenazines are example N-heteroacenes that, similar to their hydrocarbon acene analogues, exhibit desirable electronic and optoelectronic properties. Phenazines, however, are more stable, better electron acceptors (n-type materials), and more synthetically modular. The majority of phenazine derivatives synthesized to date have been linearly functionalized azaacenes while very few examples of organic materials combining phenazine and other π-conjugated functionalities are known. Developing a thorough understanding of phenazine assembly and integration into multifunctional molecules will lead to entirely new classes of organic electronic materials and significantly advance our ability to investigate fundamental relationships between size, functionality, lattice topology, and dimensionality on the properties of π-conjugated materials. The principle objectives of the proposed research are to: (1) combine experimental synthesis and first principles calculations to investigate the formation and aromaticity of simple phenazine derivatives as well as the impact of functional groups on the favorability and reversibility of phenazine condensation reactions; (2) synthesize a library of o-phenylenediamine and o-quinone functionalized building blocks that will be used in the controlled assembly of one-dimensional multifunctional phenazine derivatives and oligomers; (3) apply new knowledge from fundamental and one-dimensional phenazine studies to prepare monodisperse, two-dimensional phenazine ladders and grids. The phenazine-based multifunctional materials are expected to have unique semiconducting and optoelectronic properties with potential applications as organic field-effect transistors, photovoltaics, light-emitting diodes, and sensors.

Dr. Michelle Personick Conferred Tenure

It is with great pleasure that the Chemistry Department announces the promotion of Dr. Michelle Personick, who was conferred tenure by the Board of Trustees at its most recent meeting. In the summer of 2015, Michelle joined the faculty at Wesleyan University as an assistant professor of chemistry, where her independent research program continues to include an assortment of colorful noble metals. Dr. Personick’s research in inorganic chemistry is focused on developing tailored metal nanoparticles that function as improved catalysts for energy- and resource-efficient chemical synthesis and the clean production of energy. Her goal is to transform the overall energy landscape and offset the driving forces of climate change. She has published numerous peer-reviewed articles and one book chapter, and her work has been supported by grants from the National Science Foundation, Army Research Office, and American Chemical Society Petroleum Research Fund. Professor Personick offers courses on Principles of Chemistry II, Advanced Inorganic Chemistry, Chemistry of Materials and Nanomaterials, and Nanomaterials Laboratory. Join us in celebrating this momentous achievement!

 

Michelle Personick, Associate Professor of Chemistry

 

Dr. Carla Coste Sánchez Joins the Chemistry Department

 

 

The Chemistry Department is pleased to welcome Dr. Carla Coste Sánchez as a Visiting Assistant Professor of Chemistry. Professor Coste Sánchez holds a Chemistry degree from the University of Puerto Rico and a Ph.D. in Pharmaceutical Sciences from the University of North Carolina – Chapel Hill. Her graduate work focused on developing an orally available chelating agent for decorporation of different metals. Afterwards, she completed a year-long postdoc in the Center for Innovative Pharmacy Education (CIPhER) at UNC-CH. Her interests include science education, pharmaceutics, and drug delivery. In her down time, she enjoys hiking, camping, and various crafts like quilting.  The department is delighted to have her join us!

 

 

 

CHEM 258 Publishes Paper in Journal of Chemical Education

Anastasia Saar, Mikayla Mclaughlin, Rachael Barlow, Jeffrey Goetz, Deji Adediran, and Anisha Gupta have published a paper in J. Chem. Educ. about pivoting the Chem 258 lab to online this past spring.  The title is “Incorporating Literature into an Organic Chemistry Laboratory Class: Translating Lab Activities Online and Encouraging the Development of Writing and Presentation Skills”.  It appears in a special issue of the journal on Insights Gained While Teaching Chemistry in the Time of COVID-19.

 

Abstract

After Wesleyan University moved all classes online because of the global outbreak of SARS-CoV-2, the organic chemistry laboratory course adjusted its curriculum to fit the circumstances. A symposium project with several components was introduced, allowing students to develop their scientific writing, presentation, and critical thinking skills through the assigned quiz, reading questions, discussion forum, article summary, and oral presentation. A paper published in ACS Omega about compounds in garlic essential oil as a potential treatment for SARS-CoV-2 was chosen for literature review; many techniques used in the paper, such as distillation and GC–MS analysis, were familiar to students, and the content was relevant to both the course and current events. Presentations were given through Zoom, and all of the assignments were handed in electronically. This symposium-style project can be easily formatted for in-classroom or online learning and, on the basis of student survey data, was greatly beneficial to helping students improve key skills necessary for upper-level science courses at Wesleyan and beyond.

 

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The full text of the paper can be found at: https://pubs.acs.org/doi/10.1021/acs.jchemed.0c00727

Diverse Magazine Honors Prof. Erika Taylor

Associate Professor Erika Taylor has been named one of the “Top 35 Women in Higher Education” by Diverse magazine.  This honor recognizes women who have made significant contributions to the cause of diversity in higher education and beyond.

“Taylor, associate professor of chemistry, environmental studies and integrative sciences, joined the Wesleyan faculty in 2007. She holds a bachelor’s degree in chemistry with honors from the University of Michigan at Ann Arbor, a Ph.D. in chemistry from the University of Illinois at Urbana- Champaign and was a postdoctoral research associate at Albert Einstein College of Medicine. Throughout her career, Taylor has worked at the interface of chemistry and biology. She strives to find ways to exploit enzymes found in nature to perform reactions that can help advance the fields of chemistry and medicine. Her research group has included over 75 students to date, spanning high schoolers to Ph.D. students, with women and other underrepresented students comprising more than three-quarters of her lab members. In addition to her research, she has been a passionate advocate for diversity, lending time and energy to provide opportunities in science for female, minority and low-income students. Taylor was awarded the Binswanger Prize for Excellence in Teaching for her passion and dedication to supporting the academic and personal development of all of her students. Her track record of mentoring diverse students culminated in being named Wesleyan University’s McNair Program faculty director in 2018. Beyond Wesleyan, she founded and continues to run a Girls in Science camp for elementary through middle school aged girls, which highlights the diversity of women that exists in science and raises funds to enable nearly half of the students to participate tuition free.”

See the full story at http://newsletter.blogs.wesleyan.edu/2020/04/05/taylor-named-a-top-35-women-in-higher-education-by-diverse/ and the full list of this years’ honorees at https://diverseeducation.com/2020-Top-35-Women-in-Higher-Education/#/ .