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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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.

Vasileios Drogkaris Receives PhD

Dr. Vasileios Drogkaris

Dr. Vasileios Drogkaris successfully defended his Ph.D. thesis titled “Exploring the self-assembly of conjugated materials and the utility of the thiol-Michael reaction in macromolecular synthesis” on March 2nd, 2021. Vasili came to Wesleyan in 2014 after receiving his B.S. in chemistry from the University of Athens, Greece. While an undergraduate Vasili carried out research investigating ring-opening metathesis polymerization techniques using novel tungsten catalysts. At Wesleyan, Vasili joined the lab of Prof. Northrop and embarked on several research projects exploring the dynamic covalent self-assembly of boronic acids as well as the use of thiol-Michael reactions in macromolecular synthesis. Most prominently, Vasili developed the dynamic self-assembly of a series of boronate ester-bridged oligo(phenylene ethynylene) ladder compounds that have laid the groundwork for increasing our understanding of π-conjugation in one-dimensional versus two-dimensional materials. Vasili has recently accepted a position at Spartech, a leader in specialty plastics and packaging.


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.



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/#/ .


Chemistry Students Present at the Research and Science Poster Session 2019

The undergraduate summer research fellows presented posters on their accomplishments on July 25, 2019. Twenty-four of the presentations were on work done in the Chemistry Department, representing 8 different groups. For more on the event, visit News@Wesleyan. A list of the chemistry presenters is below the photographs.


Sydney Taylor-Klaus ’20, O’Neil Group

Leila Etemad, ’20, Personick Group

Sally Landon Tepper, ’22, Northrop Group

Amy Liu, ’20, Taylor Group

Anastasia Saar “Allosteric Regulation in the MutS Protein”
Miranda Nestor “MD Simulations of CAP to Detect Allostery without a Conformational Change”
California Clark “Natural Product Analogue Synthesis to Fight Caner”
May Do “Synthesis of Analogs of Rocaglamide via the IFB Reaction”
Alexandra Goss “Synthesis of Nigrospine”
Aryan Vavila “Investigating the Electrical Properties of Zigzag and Armchair Cyclacenes”
Sally Tepper “Study of Methyl Propiolate in Thiol-Michael ‘Click’ Reactions”
Jaina Wollowitz “A Computational Investigation of the Mechanisms of Thiol-Vinylsulfone Reaction Initiators”
Christopher Falls “The Rotational Spectra of Phenylsulfur Pentaflouride”
Valerie Balog “iPSC-derived Astrocyte and Motor Neuron Co-Culture in a Lentiviral Expression Model of SODI-A4V Amyotrphic Lateral Sclerosis”
Camille Chossis “Cell Non-Autonomous Effect of GLIA on Neurodegeneration in C9ORF72 Dependent Frontotemporal Dementia and Amytrophic Lateral Sclerosis”
Matthew Huston “Inhibition of Specific Cancer Cell Lines Using Rocaglamide Derivatives”
Daniel Kulick “Motor Neuron Specific Sensitivity to Organochlorine Pesticides”
Sydney Taylor-Klaus “Biochemical Analysis of Superoxie Dismutase I”
Leila Etemad “Generating Bimetallic Silver-Platinum Nanoprisms and Methods to Interconvert Between Nanoprisms and Bipyramids”
Abrar Habib “Plasmonic Approach to Synthesizing Bimetallic Nanoparticles as Functional Catalysts”
Claire (Jing Jin) Wang “Optimization of Palladium Nanoparticle Syntheses for the Underpotential Deposition of Silver”
Nafisa Masud “Elucidating Protein Dynamics with the Kinetic Ensemble Approach”
Nicholas Wells “Molecular Dynamics Simulations of ALS-Causing Superoxide Dismutase I Mutations”
Brynn Assignon “Creating Chimeric Proteins Using a Domain Swapping Mechanism”
Colleen Castro “Using Molecular Docking Techniques to Find an Inhibator of Heptosyltransferase I in E. coli
Amy (Zhiqi) Liu “Investigation of Kinetics and Protein Dynamics of Escherichia coli Heptosyltransferases II”
Kate Luo “Investigating the Mechanism of LigAB Catalyzed Lignin Degradation”
Kate Sundberg “The Synthesis of a Probe for Lignin Depolymerization Detection”


Tishler Pizza Party and Awards Ceremony

The 2019 Tishler Chemistry Pizza Party & Awards Ceremony was held on May 1 this year. Department Chair Westmoreland noted the following milestones and accomplishments for the department:

– The Department published 23 papers (with 37 different Wesleyan authors).
– Eight graduating seniors will receive Honors or High Honors for their senior theses.
– Six majors were elected to Phi Beta Kappa this year.
– Six M.A. students and two Ph.D. students have completed their degrees this year.

The 2019 Chemistry Department Awards were announced. Congratulations to all our award recipients!

ACS Analytical Award: Leticia Costa
Awarded for excellence in analytical chemistry
ACS Award in Inorganic Chemistry: Grace Chen
To recognize achievement in inorganic chemistry and to encourage further study in the field
ACS Award in Organic Chemistry: David Cabanero
To a student who has displayed a significant aptitude for organic chemistry
ACS Award in Physical Chemistry: Matt Erodici
To recognize achievement in physical chemistry and to encourage further study in the field
ACS Connecticut Valley Section Award: Jaquelin Aroujo
For outstanding achievement by a graduating chemistry major
American Institute for Chemists Award: Eija Kent
For outstanding achievement by a graduating chemistry major
Bradley Prize: David Cabanero and Theo Prachyathipsakul
To the senior or junior who excels in chemistry and particularly in special original work
Silverman Prize: Alison Biester
Awarded to a member of the junior or senior class for excellence in chemistry
CRC Award (General Chemistry): Megan Tran
For the outstanding first-year student in Principles of Chemistry
CRC Award (Organic Chemistry): Sally Tepper
For the outstanding first-year student in Organic Chemistry
Hawk Prize: Frank Tucci and Victoria Yu
To the students who have done the most effective work in biochemistry
Martius Yellow Award: Allie Goss and Rochelle Spencer
Awarded for excellence in Integrated Chemistry Laboratory
The Wallace C. Pringle Prize for Research in Chemistry: Alison Biester
Awarded to a student for excellence in research.
Peterson Fellowship: Cody Hecht
For graduate study in biochemistry
Tishler Prize: Vasileios Drogkaris
Awarded to the best graduate teaching assistant in chemistry

Undergraduates Present Research at ACS Section Symposium

Seven of our undergraduate majors presented their research work at the American Chemical Society Connecticut Valley Section Undergraduate Research Symposium held Apr 27 in the new science center at Amherst College. At the symposium Jacquelin Aroujo was presented with Wesleyan’s Connecticut Valley Section Award, given for outstanding achievement by a graduating chemistry major. In addition, David Cabanero received one of two prizes for the Best Poster Presentations. The students enjoyed sharing their work and hearing about what their peers at other schools are doing.

Grace Chen (’20): A 1H Relaxometric Approach to Understanding the Solution Speciation of Mn(II) Complexes in the Context of MRI Contrast Agents
Eija Kent (’19): Synthesis of Gold Alloyed Nanoparticles
Jessica Garcia (’19): Synthesis of Pyridine-Based Ligands for Use in MRI Contrast Agent Design

Abrar Habib (’21): Synthesis of Bimetallic Palladium-Copper (Pd-Cu) & Silver-Platinum (Ag-Pt) Nanoparticles
David Cabanero (’19): Investigating the Mechanism to Enantioselective Induction of the “Interrupted” Feist-Bénary Reaction
Jaquelin Aroujo (’19): An Enantioselective Synthesis of Rocaglamide via an “Interrupted” Feist-Bénary Reaction
Theo Prachyathipsakul (’19): Synthesis and Study of a Water-Soluble Macrocycle

Participants in the ACS-CVS Undergraduate Research Symposium. Seated (left to right): Jessica Garcia, Eija Kent, Grace Chen, Jaquelin Aroujo, Abrar Habib, David Cabanero, and Theo Prachyathipsakul. Standing: Professor Westmoreland

Abrar Habib with his poster waiting the start of the session.

Jaquelin Aroujo receiving the ACS-CVS Award.

David Cabanero with his winning poster.