RSS FeedUpcoming EventsDesign and evolution of artificial metalloenzymes, April 1https://events.berkeley.edu/chem/event/232513-design-and-evolution-of-artificial-metalloenzymes

Enzyme design represents a formidable challenge. We do not fully understand the rules of protein folding, and our knowledge of structure-function relationships in these macromolecules is at best incomplete. Nature has solved the problem of protein design through the mechanism of Darwinian evolution. From primitive peptidic precursors, recursive cycles of mutation, selection and amplification of molecules with favorable traits have given rise to all of the many thousands of gene products in every one of our cells. An analogous process of natural selection can be profitably exploited in silico and in the laboratory on a human time scale to create, characterize and optimize artificial catalysts for tasks unimagined by Nature. Recent progress in combining computational and evolutionary approaches for the design of artificial metalloenzymes will be discussed, together with insights into enzyme function gained from studies of the engineered catalysts.

https://events.berkeley.edu/chem/event/232513-design-and-evolution-of-artificial-metalloenzymes
Organic Chemistry Seminar, April 2https://events.berkeley.edu/chem/event/230054-organic-chemistry-seminar

James Tour, T. T. and W. F. Chao Professor, Rice University

Flash Joule Heating

Described will be ultrafast heating and cooling routes to synthesize graphene and other 2D materials, carbon nanotubes, heteroatom substituted carbons and many inorganics, all in gram to ton scales. Using the same approaches, ultrafast routes to the selective extraction of metals in electronic waste, industrial waste and metal ores, the degradation of PFAS, soil remediation and battery anode and cathode recycling will be discussed.

https://events.berkeley.edu/chem/event/230054-organic-chemistry-seminar
George C. Pimentel Memorial Lecture, April 2https://events.berkeley.edu/chem/event/230066-george-c-pimentel-memorial-lecture

Ewine F. van Dishoeck, Professor, Universiteit Leiden

Chemistry between the stars: from clouds to planets

The space between the stars is not empty but filled with a very dilute gas. In spite of the extremely low temperatures and densities, these clouds contain a surprisingly rich chemistry, as evidenced by the detection of more than 300 different molecules, from simple to complex and from gas to solid-state ices. These clouds are also the birthplaces of new stars and planets. New powerful observatories such as the Atacama Large Millimeter Array (ALMA) and the James Webb Space Telescope (Webb) have found water and a surprisingly rich variety of organic materials near forming stars, including simple sugars, ethers and alcohols. How are these molecules formed in space? Which molecular processes play a role? How common are they and can they be delivered to new planets?

https://events.berkeley.edu/chem/event/230066-george-c-pimentel-memorial-lecture
Imaging condensed counterions next to peptoid fibers / Sequence-conformation relationships of neurofilament tail domains in protein brushes, April 3https://events.berkeley.edu/chem/event/244003-imaging-condensed-counterions-next-to-peptoid-fibers-

Imaging condensed counterions next to peptoid fibers / Sequence-conformation relationships of neurofilament tail domains in protein brushes

https://events.berkeley.edu/chem/event/244003-imaging-condensed-counterions-next-to-peptoid-fibers-
Graduate Research Seminar, April 4https://events.berkeley.edu/chem/event/204471-graduate-research-seminar

Engineering Adeno-Associated Virus Vectors for Enhanced Transduction Efficiency in Astrocytes for Gene Therapy in Huntington’s Disease

https://events.berkeley.edu/chem/event/204471-graduate-research-seminar
Special Seminar: Transition Metal Catalyzed Cycloaddition Reactions to Synthesize Seven- and Eight-Membered Rings., April 4https://events.berkeley.edu/chem/event/243985-special-seminar-transition-metal-catalyzed

Many natural products and pharmaceutical compounds have complex skeletons. One of the major challenges in synthesizing these molecules is how to efficiently build the complex skeletons within. Even though there are many powerful reactions (such as the Diels-Alder reaction, Pauson-Khand reaction, and ring-closing metathesis reaction) for accessing different ring structures, new ring formation reactions, especially those complementing or surpassing previous ones, are in high demand.

To solve this challenge, my group has been endeavoring to develop new ring formation reactions. Since 2004, a dozen of ring formation reactions has been developed by us. Application of these ring formation reactions in total synthesis of natural products has been achieved by us and other leading chemists.

In this 50-minute seminar, I will discuss the development and mechanistic understanding of several transition metal catalyzed cycloadditions for constructing synthetically difficult seven- and eight-membered rings, together with the application of our [5+2+1] reaction in the synthesis of natural products.

https://events.berkeley.edu/chem/event/243985-special-seminar-transition-metal-catalyzed
Polar Topological Defects – Fundamentals to Applications: Nano Seminar series, April 5https://events.berkeley.edu/live/events/230393-polar-topological-defects-fundamentals-to

Topological defects such as vortices and skyrmions have recently gained significant interest in solid state materials as ferroic materials (ferromagnets and ferroelectrics) have become a test-bed to realize and control these nanoscale structures. Although this phenomenon is being investigated as a pathway to energy efficient information storage, broader applications in interaction of electromagnetic waves with such features are emerging.

In the case of ferroelectrics, boundary condition engineering is used to achieve vortices, skyrmions, and merons in low dimensional epitaxial oxide heterostructures.

In this talk, I will introduce the notion that similar phenomenology but at the atomic scale can be achieved in charge density wave phases, especially nominally semiconducting chalcogenides. I will outline my group and other groups’ efforts in showing non-trivial toroidal polar topologies at the atomic level in chalcogenides with nominally empty conduction band with d-orbital character such as 1T-TiSe2, Ta2NiSe5 and BaTiS3.

Specifically, we use X-ray single crystal diffraction as a probe for high quality single crystals of a quasi-1D hexagonal chalcogenide, BaTiS3, to reveal complex polar topologies such as vortices, and head-to-head and tail-to-tail arrangement of dipoles. Recent experiments and theoretical studies on the stability and dynamics of these features, and their broad connection to low dimensional magnets, will also be discussed. Lastly, I will outline the perspective for photonic applications of polarization textures.

***********

Jayakanth Ravichandran did his PhD in the Ramesh lab here at UC Berkeley (Go Bears!) and postdoc with Philip Kim at Harvard. He joined the USC faculty in 2015.

/live/events/230393-polar-topological-defects-fundamentals-to
Earl L. Muetterties Lectures in Chemistry, April 5https://events.berkeley.edu/chem/event/230507-earl-l-muetterties-lectures-in-chemistry

Karsten Meyer, Chair of Inorganic and General Chemistry, Friedrich-Alexander-Universität

“Super-Oxidized” Iron Nitrido & “Super-Reduced” Iron Nitrosyl Complexes in
tris-Carbene Coordination Spheres – and How Iron Really Feels About it

In this seminar, we will present our work on the synthesis and reactivity of metal nitrido and nitrosyl complexes. First, we report our studies on high-valent Fe(IV, V, VI, and VII) nitrido complexes, synthesized via photolytic azide and N–C bond cleavage in iron imides Fe=N–Ad, followed by oxidation with AgII and XeII-salts. In this series of complexes, the Fe/N unit is stabilized by the sterically encumbered N-anchored tris-N-heterocyclic carbene chelates tris-amine (alkyl: methyl = TIMMN; ethyl = TIMEN). Based on the iron nitrido complex [(TIMENMes)FeIV(N)]+,[1] we show how subtle changes in ligand design (TIMEN vs. TIMMN) lead to vastly different reactivity and the stabilization and isolation of air and moisture-stable stable high-valent Fe(V) and super-oxidized Fe(VI) as well as highly reactive Fe(VII) complexes.

https://events.berkeley.edu/chem/event/230507-earl-l-muetterties-lectures-in-chemistry
Tell Your Story: The Power of Your Discovery Narrative to Guide Your Future, April 8https://events.berkeley.edu/live/events/229111-tell-your-story-the-power-of-your-discovery-narrative

How do you translate your experience at Cal to your future career? This workshop is designed for graduating undergraduate students (or those worried about graduation) to reflect on what you discovered in and beyond the classroom to hone your story. Come learn how to frame your experiences to open doors for the next chapter of your life after graduation.

Offered in-person or online (60 mins). Lunch provided to first 30 attendees.

/live/events/229111-tell-your-story-the-power-of-your-discovery-narrative
Structural & Quantitative Biology Seminar, April 8https://events.berkeley.edu/chem/event/232524-structural-quantitative-biology-seminar

Structural & Quantitative Biology Seminar

https://events.berkeley.edu/chem/event/232524-structural-quantitative-biology-seminar
Organic Chemistry Seminar, April 9https://events.berkeley.edu/chem/event/230055-organic-chemistry-seminar

TBD

https://events.berkeley.edu/chem/event/230055-organic-chemistry-seminar
Physical Chemistry Seminar, April 9https://events.berkeley.edu/chem/event/230065-physical-chemistry-seminar

Amy Cordones-Hahn, Stanford PULSE Institut, SLAC National Accelerator Laboratory

Revealing the influence of redox-active ligands on the excited states and photochemistry of molecular photocatalysts using x-ray spectroscopy

Molecular photocatalysts based on first row transition metals often employ redox-active or non-innocent ligands to support multi-electron transfer reactions. Strong metal-ligand covalency or hybridization often accounts for the unique reactivity of such complexes, but it also makes the assignments of the metal and ligand contributions to the catalyst electronic structure and reactivity ambiguous. Furthermore, the impact of covalency on the excited state electronic structures of such complexes has gone largely unexplored. X-ray spectroscopy, which probes atomic core level transitions, is a well-suited technique to address these questions. The atomic specificity inherent to x-ray spectroscopy allows one to disentangle metal and ligand contributions to the catalyst electronic structure and differentiate the site of reactivity. These methods can be applied in the steady state or in the time domain, to characterize the ground state or transient electronic excited states and reaction intermediates, respectively. My group uses x-ray spectroscopy to investigate the electronic structure and reaction mechanisms of first row transition metal photocatalysts containing non-innocent ligands. In this seminar I will describe how the metal-ligand covalency of metal bis(dithiolenes) and related complexes can be quantified using a combination of metal and ligand atom x-ray spectroscopy methods and extend this idea towards characterizing the unique electronic excited states and photochemistry of these complexes.

https://events.berkeley.edu/chem/event/230065-physical-chemistry-seminar
Bioengineering Seminar: Surgical Bioengineering - Engineering Stem Cells and Extracellular Components for Tissue Regeneration, April 10https://events.berkeley.edu/live/events/217517-bioengineering-seminar-surgical-bioengineering-engine

Abstract:

This presentation is providing an overview of the ongoing research at the UC Davis School of Medicine, Center for Surgical Bioengineering (CSB). CSB focuses on engineering stem cells and biomaterials to develop novel regenerative therapies for a variety of diseases, with the focus being on the birth defect program in collaboration with the UC Davis Fetal Treatment Center and Shriners Children’s. Birth defects represent a substantial portion of pediatric morbidity and mortality. In the United States, 1 in every 33 infants is born with a congenital anomaly, and congenital anomalies comprise the largest cause of infant death. In utero surgery and stem cell therapy have the potential to revolutionize the treatment of birth defects: instead of merely treating symptoms following birth, anomalies may be treated or cured before birth. The Wang lab has been developing fetal tissue engineering approaches using different types of stem cells, stem cell-derived extracellular vesicles, and extracellular matrix-mimicking biomaterial scaffolds to engineer the fetal environment and treat a variety of birth defects before birth. One of the major projects his lab has focused on over the past decade is on developing a stem cell technology for the fetal treatment of spina bifida. His team have successfully manufactured clinical-grade placenta-derived mesenchymal stem cells (PMSCs) in the UC Davis GMP facility, acquired IND approval from the FDA, and are currently conducting a first-in-human Phase 1/2a clinical trial for the in utero treatment of spina bifida using PMSCs. The Wang lab is also working on using lipid nanoparticles to deliver mRNAs to genetically modify developing stem cells to treat genetic diseases before birth. To harness the stem cell behavior, novel integrin-based ligands identified via One-Bead One-Compound (OBOC) combinatorial technology have been applied to target stem cells and improve stem cell attachment, migration and function.

/live/events/217517-bioengineering-seminar-surgical-bioengineering-engine
Graduate Research Seminar, April 11https://events.berkeley.edu/chem/event/207008-graduate-research-seminar

Designing Diluents to Probe Cathode-Electrolyte Interphase Formation in Lithium Anode Batteries

https://events.berkeley.edu/chem/event/207008-graduate-research-seminar
Graduate Research Seminar, April 11https://events.berkeley.edu/chem/event/209316-graduate-research-seminar

Title TBA

https://events.berkeley.edu/chem/event/209316-graduate-research-seminar
Tell Your Story: The Power of Your Discovery Narrative to Guide Your Future, April 11https://events.berkeley.edu/live/events/229112-tell-your-story-the-power-of-your-discovery-narrative

How do you translate your experience at Cal to your future career? This workshop is designed for graduating undergraduate students (or those worried about graduation) to reflect on what you discovered in and beyond the classroom to hone your story. Come learn how to frame your experiences to open doors for the next chapter of your life after graduation.

Offered in-person or online (60 mins). Lunch provided to first 30 attendees.

/live/events/229112-tell-your-story-the-power-of-your-discovery-narrative
Society of Women Engineers (SWE) Overnight Host Program, April 12https://events.berkeley.edu/chem/event/243976-society-of-women-engineers-swe-overnight-host

Hosted by the Berkeley Chapter of the Society of Women Engineers, the Overnight Host Program (OHP) is a unique event specifically for women and non-binary students admitted to UC Berkeley’s College of Engineering and Chemical Engineering majors from the College of Chemistry to get a taste of life as a Berkeley Engineer. Through engaging mixers, panels, and speakers, attendees have an exclusive chance to engage with prospective and present current engineering students, meet trailblazing professors and faculty, and be paired up with a current engineering student at UC Berkeley. We have an exciting lineup planned that you won’t want to miss out on!

Registrations* open 3/28 at: http://tinyurl.com/ohp24registration


*Register for the In-Person OHP program by Sunday, April 7th. If you would like to attend the overnight portion of the in person program please register for those by Friday, April 5th. Other programs like the virtual Pen Pal program, and the Online OHP program are also available on the registration form for those who cannot attend in person!

https://events.berkeley.edu/chem/event/243976-society-of-women-engineers-swe-overnight-host
Dynamic Control Of Active Matter: Nano Seminar Series, April 12https://events.berkeley.edu/live/events/229975-dynamic-control-of-active-matter-nano-seminar

Through the magic of ‘active matter,’ which converts chemical energy into mechanical work to drive emergent properties, biology solves a myriad of seemingly impossible physical challenges. I will present my lab’s efforts to develop new fluid mechanics models to direct the flow of matter enabled by the use of “active” molecules found within living systems.

We design 2D composite materials with tunable inclusions of lipid domains embedded within an active elastic network. These mechanoresponsive lipid inclusions enable exquisite control over the phase separation and material properties (like failure resistance) of 2D composite materials. I will also present our recent work on model predictive control and learning of many-body colloidal interactions driven by active and hydrodynamic forces.

**********

Sho Takatori did his PhD at CalTech and postdoc as a Miller Fellow here at UCB (Go Bears!). He joined the UCSB faculty in 2020. Awards include a Packard Fellowship and the ACS New PI.

/live/events/229975-dynamic-control-of-active-matter-nano-seminar
Special Seminar, April 12https://events.berkeley.edu/chem/event/243712-special-seminar

Prof. Lucia Banci - University of Florence

Metal trafficking in the cell: combining the atomic resolution with the cellular dimension

Host: Chris Chang and Sabeeha Merchant

https://events.berkeley.edu/chem/event/243712-special-seminar
Earl L. Muetterties Lectures in Chemistry, April 12https://events.berkeley.edu/chem/event/230508-earl-l-muetterties-lectures-in-chemistry

Karsten Meyer, Chair of Inorganic and General Chemistry, Friedrich-Alexander-Universität

Seminar 2 of 2

From Uranium-Mediated Small Molecule Activation and the Electrocatalytic Production of H2 from Water to Redox-Flow-Batteries

In our efforts to activate small molecules of industrial and biological concern, we have turned our attention to reactive uranium coordination complexes. Employing the chelating triazacyclononane- and single N- as well as the arene-anchored aryloxide ligands (ArO)3tacn3–, (ArO)3N3–, and (ArO)3mes3–have provided access to reactive coordination compounds of uranium in oxidation states II, III, IV, V, and VI with tailorable steric and electronic profiles. These complexes display a pronounced selectivity and reactivity in reactions with CO2 and related small heteroallenes. As a result, they provide unique reaction pathways inaccessible to d-block metals.

Here, we briefly summarize our work on CO2 activation, including a previously unknown coordination mode, stoichiometric reductive cleavage, insertion reactions, and CO2 functionalization chemistry via multiple bond metathesis. We also report the stoichiometric and catalytic “disproportionation” of CO2 to CO and CO32– via an unusually reactive µ-oxo-bridged complex. In a similar strategy, we could isolate oxalates, thiooxalates, and mixed carbonates by reacting bridged chalcogenide complexes U‒E‒ U (E = O, S, Se) with CO2, CS2, and COS.

Employing the arene-anchored chelate allowed us to elucidate the molecular and electronic structure of a new oxidation state, namely U(II), in uranium coordination chemistry. In anionic [U(OArAd,Me)3mes)]⊝, the U(II) center is supported by δ back bonding. Further studies of [U(OArAd,Me)3mes)]0/– revealed unique electrochemical behavior, rendering these complexes candidates for electrocatalysis. Accordingly, [U(OArAd,Me)3mes)] was found to be the first molecular uranium catalyst for catalytic H2 production. Utilization of this catalyst during H2O electrolysis lowered the overpotential by 0.5 V, increased the steady-state electrolysis current by a factor of 10, and lowered the faradaic resistance by three orders of magnitude. Isolation of key intermediates allowed us to determine the reaction mechanism of H2O reduction. Notably, no radicals are involved, rendering this catalyst remarkably durable. This reactivity was also studied with a series of lanthanide complexes [Ln(OArAd,Me)3mes)] as well, which permits for fine-tuning of overpotential by choice of the lanthanide ion.

Finally, our previous electrochemical studies on redox complex pairs such as [U((OAr)4cyclen)] and other simple [U(acac)4] derivatives, with electrochemical windows of up to ca. 4 V, initiated a project to design a redox-flow battery (RFB). Accordingly, an all-uranium-based electrochemical cell was constructed with [UIV/V]0/+ and [UIII/IV]−/0 complexes as anolyte and catholyte species. These complexes have favorable properties for RFB applications, including reversible redox chemistry, relatively high stability toward electrochemical cycling, and high solubility in common organic solvents. A proto-type cell provides a promising entry point to a potential future class of uranium-based, non aqueous redox-flow battery electrolytes, not for use in personal devices but incorporated into under ground energy storage systems, e.g., foundations of wind turbines, where weight and radioactivity levels are not an issue and where this abundant waste material could find new application.

https://events.berkeley.edu/chem/event/230508-earl-l-muetterties-lectures-in-chemistry
Structural & Quantitative Biology Seminar, April 15https://events.berkeley.edu/chem/event/206994-structural-quantitative-biology-seminar

Structural & Quantitative Biology Seminar

https://events.berkeley.edu/chem/event/206994-structural-quantitative-biology-seminar
Organic Chemistry Seminar, April 16https://events.berkeley.edu/chem/event/230056-organic-chemistry-seminar

TBD

https://events.berkeley.edu/chem/event/230056-organic-chemistry-seminar
Physical Chemistry Seminar, April 16https://events.berkeley.edu/chem/event/230064-physical-chemistry-seminar

Bingqing Chen, Assistant Professor of Chemistry, University of California Berkeley

Predicting materials properties with the help of machine learning

I will demonstrate how to enable ab initio predictions of materials properties by combining advanced statistical mechanics with machine learning interatomic potentials. I will show example applications on computing phase diagrams, chemical potentials of liquid mixtures, adsorption isotherms of gas in porous materials, and reactions on surfaces.
https://events.berkeley.edu/chem/event/230064-physical-chemistry-seminar
Bioengineering Seminar: Engineering Extracellular Matrix Viscoelasticity to Probe Cellular Responses, April 17https://events.berkeley.edu/live/events/229420-bioengineering-seminar-engineering-extracellular-matr

Abstract:

In the body, cells are surrounded by a scaffolding of biopolymers that provide physical support and biochemical cues, known as the extracellular matrix (ECM). Hydrogel cell culture models have been used to reveal that properties of the ECM, notably matrix stiffness, can regulate a host of cellular behaviors, such as migration, division, differentiation, and even cancer progression. ECM is often viscoelastic, displaying stress relaxation in response to strain, and recapitulating complex aspects of native ECM, such as dynamic remodeling and viscoelasticity, remains challenging. Further, key aspects of mechanotransduction, such as the effect of mechanics on the epigenome, are not well understood. In this talk, I will discuss how matrix stiffness can induce epigenomic remodeling leading to a tumorigenic phenotype in a breast cancer model. I will also describe our work to develop 3D hydrogel platforms that allow for dynamic tuning of matrix viscoelasticity to better understand the biological impact and pathways involved in mechanotransduction.

/live/events/229420-bioengineering-seminar-engineering-extracellular-matr
Organic Chemistry Special Seminar, April 18https://events.berkeley.edu/chem/event/243748-organic-chemistry-special-seminar

Speaker: Dr. Andrew T. Parsons, Director of Process Development, Amgen Inc.


Title: Development of a commercial manufacturing process for sotorasib, a first-in-class KRASG12C inhibitor


Abstract: Atropisomeric molecules have recently gained significant attention in pharmaceutical discovery research. Due to the increased complexity, atropisomeric active pharmaceutical ingredients (APIs) pose a significant challenge for the development of efficient, large-scale manufacturing processes. LUMAKRASTM(sotorasib), an atropisomeric API, was the first KRASG12C inhibitor to enter clinical trials and receive FDA accelerated approval. The Amgen process development team developed a chromatography-free preparation of sotorasib by leveraging high-throughput experimentation, kinetic analysis, and modeling. The final process enabled the preparation of an atropisomeric precursor to sotorasib with >99.95% enantiopurity on a multi-hundred-kilogram scale. Optimization of the downstream processing steps reduced impurity formation and improved manufacturing cycle times, which resulted in improved API quality and manufacturing efficiency. These efforts resulted in the rapid development of a manufacturing process that enabled commercialization of sotorasib at an industry-leading speed while improving environmental sustainability.

https://events.berkeley.edu/chem/event/243748-organic-chemistry-special-seminar
Inorganic Chemistry Seminar, April 19https://events.berkeley.edu/chem/event/230509-inorganic-chemistry-seminar

Amy Rosenzweig, Professor, Northwestern University

Particulate methane monooxygenase structure in situ

Under the mounting threat of climate change, increasing atmospheric methane concentrations are a constant source of concern and debate. Conversion of methane to desirable fuels and chemicals could simultaneously mitigate global warming and meet increasing energy demands. Industrial catalysts that can selectively activate the 105 kcal mol-1 C-H bond in methane require high temperatures and pressures, along with significant capital expenses. The use of biocatalysts produced by methanotrophic bacteria provides an environmentally friendly alternative. The primary biocatalyst in methanotrophic bacteria is the copper-dependent, membrane-bound enzyme particulate methane monooxygenase (pMMO). Any use of methanotrophs for biological gas-to-liquids conversion or for bioremediation requires a detailed understanding of pMMO structure and function. Despite extensive research, the molecular details of the pMMO copper active site remain controversial, in part because the enzyme loses activity upon isolation from methanotroph membranes. Thus, it is critical to structurally characterize pMMO in its native cellular environment. Our quest to achieve molecular characterization of pMMO in situ will be discussed.

https://events.berkeley.edu/chem/event/230509-inorganic-chemistry-seminar
CARA 10th Anniversary Symposium, April 22https://events.berkeley.edu/chem/event/242554-cara-10th-anniversary-symposium

Celebrate a decade of groundbreaking research in real-world technology applications.

Hear from:

  • Renowned keynote speakers

  • Leading researchers from CARA and BASF in collaborative presentations

  • Inspiring student presentations

  • Engaging panel discussion

Network with fellow researchers and industry leaders.

Register now to learn more about CARA and BASF!

(The registration page will close on 04/05/24)

 

Co-hosted by the University of California, Berkeley, and BASF.

Event Information Page

https://events.berkeley.edu/chem/event/242554-cara-10th-anniversary-symposium
Cynthia A. Chan Memorial Lecture, April 22https://events.berkeley.edu/chem/event/224072-cynthia-a-chan-memorial-lecture

Cynthia A. Chan Memorial Lecture

https://events.berkeley.edu/chem/event/224072-cynthia-a-chan-memorial-lecture
Clayton H. Heathcock Lecture in Organic Chemistry, April 23https://events.berkeley.edu/chem/event/230057-clayton-h-heathcock-lecture-in-organic-chemistry

Stephen Buchwald, Camille Dreyfus Professor of Chemistry, MIT

Catalytic Processes for Organic Synthesis

The availability of general methods for carbon-carbon and carbon-heteroatom bond formation is central to modern-day organic synthesis. This lecture will focus on aspects of the work from our labs at MIT. It will describe several Pd or Cu-catalyzed transformations relevant to the construction of molecular types of interest to those in academia and the pharmaceutical industry. A significant focus of the talk will be on the design, synthesis, and utilization of new ligands that can be used in a synthetically meaningful context.

https://events.berkeley.edu/chem/event/230057-clayton-h-heathcock-lecture-in-organic-chemistry
Chandler Lecture in Physical Chemistry, April 23https://events.berkeley.edu/chem/event/230063-chandler-lecture-in-physical-chemistry

Eugene Shakhnovich, Roy G. Gordon Professor, Harvard University

Biophysical journeys on fitness landscapes: from atoms to populations and back

I will present recent theoretical and experimental developments aimed at understanding the two-way link between protein stability and protein evolution. At the heart of these developments are models of evolutionary dynamics that merge molecular mechanisms of protein stability and folding with population genetics. Traditional population genetics models are agnostic to the physical-chemical nature of mutational effects. Rather they operate with an a’priori assumed distributions of fitness effects (DFE) of mutations from which evolutionary dynamics are derived. Alternatively some population genetics models aim to derive DFE from evolutionary observations. In departure with this tradition the novel multiscale models integrate the molecular effects of mutations on physical properties of proteins, most notably their stability, into physically intuitive yet detailed genotype-phenotype relationship (GPR) assumptions. I will present a range of models from simple analytical diffusion-based model on biophysical fitness landscapes to more sophisticated computational models of populations of model cells where genetic changes are mapped into molecular effects using biophysical modeling of proteins and ensuing fitness changes determine the fate of mutations in realistic population dynamics. Examples of insights derived from biophysics-based multiscale models include parameter-free prediction of distribution of protein stabilities in natural proteomes that explains the observation of “marginal stability” of proteins without resorting to unproven stability-activity tradeoffs, the fundamental limit on mutation rates in living organisms, physics of thermal adaptation, co-evolution of protein interactions and abundances in cytoplasm and related results, some of which I will present and discuss.

Next, I will describe “bottom-up experimental efforts to establish the relationship between biophysical properties of proteins (stability, activity, interactions with other proteins) and fitness. The approach is based on introducing rational introducing genetic variation on the chromosome of E.coli using genome editing approaches with subsequent concurrent evaluation of biophysical effects of mutations in vitro and fitness effect of strains that have these genetic variants in their chromosome. Carrying out this program for two genes encoding essential metabolic enzymes in E. coli – folA and adk – we obtained deep insights into the relationship between protein stability and fitness. In particular we quantitatively determined how the changes in stability affect the protein turnover in cellular environment resulting in changes in the abundance of functional protein and through that affecting the phenotype (growth rates and lag times). We established fundamental role of protein quality control – chaperone GroEL and certain proteases that modulate the fitness effects of stability-changing mutations in a predictable way. We developed a dynamic steady state theory that describes stability-dependent protein turnover and established the relationship between protein abundance and stability that is different from simple equilibrium Boltzmann distribution. These advances allowed us to get a comprehensive biophysical fitness landscapes for metabolic enzymes. Further we applied these advances to the analysis of antibiotic resistance in DHFR encoded by folA. The theory allowed predicting fitness effect of escape mutations in DHFR and IC50 against antibiotic trimethoprim with very high accuracy based only on biophysical molecular properties of numerous DHFR mutants. Altogether these results provide a clear picture of interplay between biophysical traits and evolutionary dynamics on various time scales – from evolution of modern proteomes to evolution of antibiotic resistance and provides practical tools to address the problem of pathogen escape from stressors from a fundamental physical-chemical perspective.

https://events.berkeley.edu/chem/event/230063-chandler-lecture-in-physical-chemistry
Printing Functional Polymers for Sustainable Earth and Habitable Mars: Nano Seminar series, April 26https://events.berkeley.edu/live/events/229388-printing-functional-polymers-for-sustainable-earth

Printing technologies have the potential to revolutionize manufacturing of electronic and energy materials by drastically reducing the energy cost and environmental footprint while increasing throughput and agility. For instance, printing organic solar cells can potentially reduce energy payback time from 2-3 years to as short as 1 day! At the same time, additive manufacturing of such functional materials brings a new set of challenges demanding exquisite control over hierarchical structures down to the molecular-scale.

We address this challenge by understanding the evaporative assembly pathway and flow-driven assembly central to all printing processes. We discover a surprising chiral liquid crystal mediated assembly of achiral semiconducting polymers in an evaporating meniscus. We uncover the molecular assembly mechanism and further show that the chiral helical structures can be largely modulated by controlling printing regimes.

Such new topological states of semiconducting polymers can empower unprecedented control over charge, spin, and exciton transport, reminiscent of how Nature efficiently transfers electrons and transduces energy using chiral helical structures. The ability to control non-equilibrium assembly during printing sets the stage for dynamically modulating assembled structures on the fly.

We demonstrate this concept by programming nanoscale morphology and structure color of bottlebrush block copolymers during 3D printing. This approach holds the potential to reduce the use of environmentally toxic pigments by printing structure color. Complementing the above hypothesis-driven approach, we are pursuing data-science driven approach to drastically accelerate discovery and manufacturing of functional polymers. By linking automated synthesis, testing, and machine learning in a close-loop, we are able to optimize function highly efficiently while discovering new physical insights for transferring closed-loop optimization into hypothesis driven discovery.

***********

Ying Diao did her PhD at MIT and postdoc at Stanford. She won many early-career awards from NSF, Sloan, NASA, ACS, etc., and is an Advanced Materials “Rising Star”. She joined UIUC in 2015.

/live/events/229388-printing-functional-polymers-for-sustainable-earth
Inorganic Chemistry Seminar, April 26https://events.berkeley.edu/chem/event/230510-inorganic-chemistry-seminar

TBD

https://events.berkeley.edu/chem/event/230510-inorganic-chemistry-seminar
Structural & Quantitative Biology Seminar, April 29https://events.berkeley.edu/chem/event/209985-structural-quantitative-biology-seminar

Structural & Quantitative Biology Seminar

https://events.berkeley.edu/chem/event/209985-structural-quantitative-biology-seminar
Organic Chemistry Seminar, April 30https://events.berkeley.edu/chem/event/230058-organic-chemistry-seminar

TBD

https://events.berkeley.edu/chem/event/230058-organic-chemistry-seminar
William A. Lester Lecture, April 30https://events.berkeley.edu/chem/event/230062-william-a-lester-lecture

Alán Aspuru-Guzik, Professor, University of Toronto

https://events.berkeley.edu/chem/event/230062-william-a-lester-lecture
cDIBS, May 2https://events.berkeley.edu/chem/event/241084-cdibs

Annual Department of Chemistry Climate Survey and the Chemistry Departmental Information and Brainstorming Session (cDIBS)

https://events.berkeley.edu/chem/event/241084-cdibs
Inorganic Chemistry Seminar, May 3https://events.berkeley.edu/chem/event/230511-inorganic-chemistry-seminar

Lisa Olshansky, LEAP Scholar & Assistant Professor, University of Illinois

Emergent Properties from Dynamicity: Investigating Conformational Control in Biomimetic Inorganic Systems

From the reduction of dinitrogen to the oxidation of water, the chemical transformations catalyzed by metalloenzymes underpin global geo- and biochemical cycles. These reactions represent some of the most kinetically and thermodynamically challenging processes known. Interestingly, rate-limiting conformational changes precede catalysis in many metalloenzymes. The pervasiveness of this mechanistic pattern suggests that conformational gating may play an important role in mediating challenging chemical transformations in an energy-efficient manner. However, these enzymes are extremely complex, rendering direct examination of their conformational gating steps a tremendous challenge. Instead, we have taken the unique approach of preparing model systems in which macroscopic changes in the molecular structure of a ligand or protein host give rise to subatomic changes in the electronic structure of a bound metal ion. These systems include both conformationally dynamic coordination complexes and conformationally switchable artificial metalloproteins. In both cases, exciting new properties have emerged from the structural dynamicity at play. Ultimately, our work with these systems aims to define and quantify the kinetic and thermodynamic consequences of conformational gating mechanisms. Additionally, the systems under development are molecular switches and can also be exploited in applications ranging from solar energy conversion, to biomedical imaging, to green methods in chemical catalysis.

https://events.berkeley.edu/chem/event/230511-inorganic-chemistry-seminar
Organic Chemistry Seminar, May 7https://events.berkeley.edu/chem/event/230059-organic-chemistry-seminar

TBD

https://events.berkeley.edu/chem/event/230059-organic-chemistry-seminar
Spring 2024 Campuswide Ceremony, May 11https://events.berkeley.edu/live/events/243373-spring-2024-campuswide-ceremony

Congratulations, Class of 2024! The campuswide Commencement for all undergraduate and graduate students, in every school and college, is on Saturday, May 11, 2024, at 10:30 a.m. at California Memorial Stadium. Check commencement.berkeley.edu for updates on how to have a smooth, memorable experience.

/live/events/243373-spring-2024-campuswide-ceremony