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Surendranath and Willard (continued)
Dr. Surendranath carried out undergraduate studies at the University of Virginia and received his PhD in Inorganic Chemistry from MIT under the direction of Professor Daniel Nocera.
Dr. Willard carried out his undergraduate studies in Chemistry and Mathematics at the University of Puget Sound and received his PhD from the University of California, Berkely under Professor David Chandler.
Dr. Surendranath's research interests span inorganic and materials chemistry with an emphasis on electrochemical methods for energy storage and utilization.
The Surendranath lab will focus on understanding and manipulating the chemistry of solid-liquid interfaces in order to develop next generation catalysts for advanced energy conversion technologies.
Dr. Willard’s training is in theoretical chemistry and his research interests generally include problems in renewable energy. Specifically, he is interested in combining the methods of quantum dynamics with those of statistical mechanics in order to elucidate the role of molecular disorder on the dynamics of photoexcited electrons.
Another longstanding research interest of Dr. Willard is the topic of aqueous solvation. In this area, the Willard lab will seek to uncover the molecular-level details of the intrinsic water interface. In particular, his group seeks to characterize the influence of solute chemistry and topology on the molecular structure of the water interface along with its associated role in a range of interface-mediated phenomena. |
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(Johnson Lab continued) As a result, new approaches to access functional monolayers could drastically augment current surface modification methods. We report the use of addressable N-heterocyclic carbenes (ANHCs) as a new class of surface anchors. ANHCs offer a potentially ideal combination of synthetic versatility, strong surface binding, and electrical conductivity that could make them the ideal platform for modern technologies that rely on molecular scale surface modification. |
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The Awards Committee of the Royal Society of Chemistry’s (RSC) Dalton Division has selected Professor Christopher C. Cummins for the 2013 RSC Ludwig Mond Award. Professor Cummins has been selected for his work in unparalleled synthetic, mechanistic, and reactivity studies of low-coordinate early-transition or actinide metal complexes containing unusual main-group ligands to discover novel chemistry of small molecules including N2, N2O, CO, CO2, and P4.
A lectureship is associated with the award and Professor Cummins will deliver lectures at several universities within the UK in the fall of 2013 and spring of 2014. |
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Pentelute Lab: We report the discovery of a facile transformation between perfluoroaromatic molecules and a cysteine thiolate, which is arylated at room temperature. This new approach enabled us to selectively modify cysteine residues in unprotected peptides, providing access to variants containing rigid perfluoroaromatic staples. |
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Mechanistic studies of an unprecedented enzyme-catalyzed 1,2-phosphono migration reaction
Drennan Lab: In Nature (April 4, 2013 issue), Ben Liu’s lab at UT Austin in collaboration with the Drennan lab at MIT published a structure-based mechanistic study of the non-heme iron enzyme (S)-2-Hydroxypropylphosphonate ((S)-2-HPP) epoxidase (HppE). More>>
They found that in addition to catalyzing an unusual dehydrogenation reaction that converts the secondary alcohol of (S)-2-HPP to the epoxide ring of the antibiotic fosfomycin, HppE is also able to catalyze a biologically unprecedented 1,2-phosphono migration with the alternative substrate (R)-1-HPP. This paper was highlighted with a New and Views, entitled “Positive and Radical,” by Spencer C. Peck and Wilfred A. van der Donk. |
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Atomic structure and hierarchical assembly of a cross-β amyloid fibril
PNAS: Anthony W. P. Fitzpatricka, Galia T. Debelouchina, Marvin J. Bayro, Daniel K. Clare, Marc A. Caporini, Vikram S. Bajaj, Christopher P. Jaroniec, Luchun Wang, Vladimir Ladizhansky, Shirley A. Müller, Cait E. MacPhee, Christopher A. Waudby, Helen R. Mott, Alfonso De Simone, Tuomas P. J. Knowles, Helen R. Saibil, Michele Vendruscolo, Elena V. Orlova, Robert G. Griffin, and Christopher M. Dobson. To read the publication, click here. To read write-up in Physicstoday, click here |
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PNAS Cover: March 26, 2013, vol. 110 no. 13
Dincă / Griffin Labs:
Pictured is a thiophene-based covalent organic framework (COF), a class of polymeric crystalline material. Thiophene is one of the most popular building blocks of conductive organic polymers but had not been previously incorporated into COFs. Guillaume H. V. Bertrand et al. synthesized and characterized COFs that included materials made from various thiophene compounds. The findings could help develop thiophene-based COFs that could be used in a variety of electronic devices, including sustainable batteries and photovoltaics. To read the publication, click here. |
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New solar-cell design based on dots and wires
Bawendi Lab: MIT researchers improve efficiency of quantum-dot photovoltaic system by adding a forest of nanowires. Using exotic particles called quantum dots as the basis for a photovoltaic cell is not a new idea, but attempts to make such devices have not yet achieved sufficiently high efficiency in converting sunlight to power. MIT News office>> |
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Study offers new way to discover HIV vaccine targets
Chakraborty Lab: Ragon Institute researchers develop a method to identify weak points in viral proteins that could be exploited for vaccine development. Decades of research and three large-scale clinical trials have so far failed to yield an effective HIV vaccine, in large part because the virus evolves so rapidly that it can evade vaccine-induced immune responses.
MIT News Office>> |
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| The Jamison group has recently reported a novel, air-stable nickel(II) precatalyst for the internally-selective coupling of substituted benzyl chlorides with terminal alkenes. The reaction is operationally simple, can be carried out on the benchtop with no purification or degassing of solvents or reagents, and requires no exclusion of air or water during setup. Synthesis of the precatalyst is accomplished through a straightforward procedure that employs inexpensive, commercially available reagents, requires no purification steps, and proceeds in high yield. |
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Synthesis and Anticancer Activity of Epipolythiodiketopiperazine Alkaloids
N. Boyer, K. C. Morrison, J. Kim,
P. J. Hergenrother, and M. Movassaghi*
Chem. Sci. 2013 DOI: 10.1039/C3SC50174D |
| Movassaghi Lab: The total synthesis of a large set of epipolythiodiketopiperazine (ETP) alkaloids enabled their evaluation against cancer cell lines in culture providing the first expansive structure–activity relationship to be defined for monomeric and dimeric ETP-containing natural products and their synthetic cognates. While many ETP derivatives demonstrate potent anticancer activity across a broad range of cancer cell lines and kill cancer cells via induction of apoptosis, they are not active against normal human erythrocytes. Go to MIT News>> |
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The ACS Division of Inorganic Chemistry and Inorganic Chemistry have announced that Professor Christopher C. Cummins is the winner of the inaugural Inorganic Chemistry Lectureship Award.
Professor Cummins was nominated by his peers for his creativity, rigor and record of research success in the field of inorganic chemistry. |
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Professor Elizabeth M. Nolan has been awarded a 2013 Sloan Research Fellowship.
Sloan Research Fellowships are given to early-career scientists and scholars whose achievements and potential identify them as rising stars among the next generation of scientific leaders. This year’s recipients are drawn from 61 colleges and universities across the United States and Canada. Go to MIT News>> |
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Professor Brad L. Pentelute has been selected to receive a Damon Runyon-Rachleff Innovation Award.
The award is designed to provide support for the next generation of exceptionally creative thinkers with “high-risk/high-reward” ideas that have the potential to significantly impact our understanding of and/or approaches to the prevention, diagnosis or treatment of cancer. |
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Control of Substrate Access to the Active Site in Methane Monooxygenase
Seung Jae Lee, Michael S. McCormick, Stephen J. Lippard &
Uhn-Soo Cho
Nature (2013) doi:10.1038/nature11880
Published online 10 February 2013 |
| Lippard Lab: Methanotrophs consume methane as their major carbon source and have an essential role in the global carbon cycle by limiting escape of this greenhouse gas to the atmosphere. These bacteria oxidize methane to methanol by soluble and particulate methane monooxygenases (MMOs).Soluble MMO contains three protein components, a 251-kilodalton hydroxylase (MMOH), a 38.6-kilodalton reductase (MMOR), and a 15.9-kilodalton regulatory protein (MMOB), required to couple electron consumption with substrate hydroxylation at the catalytic diiron centre of MMOH2. |
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Bawendi Lab: New production method could enable everything from more efficient computer displays to enhanced biomedical testing.
Quantum dots — tiny particles that emit light in a dazzling array of glowing colors — have the potential for many applications, but have faced a series of hurdles to improved performance. But an MIT team says that it has succeeded in overcoming all these obstacles at once, while earlier efforts have only been able to tackle them one or a few at a time. Go to MIT News>> |
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Ting Lab: A report in Science describes new methodology for mapping the proteomic composition of specific organelles in living cells. The method uses a promiscuous biotinylating enzyme, called APEX, that can be genetically targeted to cellular regions of interest, and tags proximal proteins for subsequent mass spectrometric identification.Lead authors Hyun-Woo Rhee and Peng Zou used the methodology to map the proteome of the human mitochondrial matrix, identifying 495 proteins with exceptional specificity.
Go to MIT News>> |
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| Johnson Lab: Growing pores: Exposure of a bis-norbornene trithiocarbonate to long-wavelength UV light, or sunlight, in the presence of N-isopropylacrylamide (NiPAAm) led to well-defined norbornene–telechelic poly(NiPAAm) macromers. The macromers were end-linked with a tris-tetrazine via inverse electron demand Diels–Alder cycloaddition to generate polymer gels. Addition of new monomer, followed by exposure to sunlight, lead to "photo-growth" of the network pores. The photo-growth process represents a novel strategy for conversion of sunlight energy to mass in bulk materials, and opens the door to photo-controlled preparation of bulk polymer networks with both mechanical and chemical three-dimensional composition gradients. Click here to read the publication in Angewandte Chemie |
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A step toward stronger polymers - Counting loops that weaken materials could help researchers eliminate structural flaws.
Johnson Lab: Many of the objects we encounter are made of polymers — long chains of repeating molecules. Networks of polymers form manmade materials such as plastics, as well as natural products such as rubber and cellulose.
Within all of these polymeric materials, there are structural flaws at the molecular level. To form an ideal network, each polymer chain would bind only to another chain. However, in any real polymeric material, a significant fraction of the chains instead bind to themselves, forming floppy loops. Click here to go to MIT News Office.
Paper highlighted in Nature
http://www.nature.com/nature/journal/v493/n7431/full/493172a.html |
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| Ting Lab: Single-molecule fluorescence imaging of cellular proteins provides rich information about protein dynamics. Quantum dots are uniquely suitable for single-molecule detection because they are brighter and more photostable compared to small molecule fluorophores and fluorescent proteins. The Ting Lab extended their PRIME methodology (for PRobe Incorporation Mediated by Enzymes) to the targeting of quantum dots to cellular proteins. This new method features covalent quantum dot attachment and requires only a small tag fusion to the protein of interest, and is therefore advantageous compared to several established methods. Quantum dot targeting by PRIME was used to study lateral protein diffusion on the cell surface, as a readout of potential protein-protein interactions. Click here to read the paper. |
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 In this electron microscope image of a mitochondrion, the matrix has been stained with APEX, making it appear dark. The lighter projections into the matrix represent the intermembrane space.
Image: Tom Deerinck and Jeff Martell
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Ting lab: Protein-labeling technique allows high-resolution visualization of molecules inside cells.
The glowing green molecule known as green fluorescent protein (GFP) has revolutionized molecular biology. When GFP is attached to a particular protein inside a cell, scientists can easily identify and locate it using fluorescence microscopy. However, GFP can’t be used with electron microscopy, which offers much higher resolution than fluorescence microscopy.
Chemists from MIT have now designed a GFP equivalent for electron microscopy — a tag that allows scientists to label and visualize proteins with unprecedented clarity. Go to MIT News>> |
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Members of the Department of Chemistry recently learned the devastating news that chemistry graduate student, Allison Tovo-Dywer, passed away on October 11, 2012, after a year-long battle with cancer. She was 25 years old.
Allison came to MIT from Minnesota. She earned her undergraduate degree from the University of Chicago and was a third year doctoral student under the research supervision of Professor Arup Chakraborty. Allison was working in Professor Chakraborty's group on developing and applying approaches rooted in statistical physics to understand the human immune response to HIV infections. Her work involved collaborations with clinician scientists at Mass General Hospital, and its ultimate goal was to harness a mechanistic understanding of the human immune response to help design vaccines and therapies against scourges on the planet, for example HIV. Allison consistently exhibited kindness and warmth to those around her, for example by graciously volunteering her time as a graduate student mentor, helping first-year graduate students with questions about graduate student life and research. Allison will be greatly missed. Our deepest sympathies are with Allison's family, friends, and the faculty and staff who knew her.
Professor Chakraborty will be traveling to Chicago to attend a privately organized memorial service for Allison on Saturday, October 20th. Expressions of condolence may be brought to the Department of Chemistry Graduate Administrator Jennifer Weisman in Room 2-204 by the end of the day on Monday, October 22nd and she will be glad to send them to Allison's family. At this time we are respecting the privacy of her family and waiting for information on how they would like us to best communicate her passing more broadly and honor her life, as well as any additional plans for remembrance. |
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Devices Go Nose to Nose With Bomb-Sniffer Dogs
Swager Lab's FIDO featured in the New York Times. Click here to read the article________________________________________________________________________________
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Swager Lab: Carbon nanotubes offer a powerful new way to detect harmful gases in the environment. However, the methods typically used to build carbon nanotube sensors are hazardous and not suited for large-scale production.
A new fabrication method created by MIT chemists — as simple as drawing a line on a sheet of paper — may overcome that obstacle. MIT postdoc Katherine Mirica has designed a new type of pencil lead in which graphite is replaced with a compressed powder of carbon nanotubes. The lead, which can be used with a regular mechanical pencil, can inscribe sensors on any paper surface. Go to MIT News Office to read more and to see a video presentation. |
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Johnson Lab: A new “brush-first” strategy for star polymer synthesis is described. In this method, ring-opening metathesis polymerization of a norbornene–PEG macromonomer generates small living brush initiators. Transfer of various amounts of this brush initiator to vials containing a photocleavable bis-norbornene cross-linker yielded a series of water-soluble “brush-arm star polymers” (BASPs) with low polydispersities and molecular weights that increased geometrically as a function of the amount of bis-norbornene added. The BASP cores could be cleaved upon exposure to UV light; the extent of photo-disassembly depended on the amount of cross-linker. EPR spectroscopy of nitroxide-labeled BASPs was used to probe differences between the BASP core and surface environments. We expect that BASPs will find applications as easy-to-synthesize, stimuli-responsive core–shell nanostructures. Click here to read the paper. |
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Drennan Lab: Indolocarbazoles are a class of natural products that have undergone multiple clinical investigations for their therapeutic activities. The Reb and Sta biosynthetic pathways that generate compounds rebeccamycin and staurosporine, respectively, have been largely elucidated with a few exceptions. In the most recent edition of Chemistry and Biology, the Drennan lab has published findings clarifying the role of FAD in the important branch point enzymes, RebC and StaC. To read the paper, click here. |
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The editors of Technology Review have chosen Professor Mircea Dincă to be one of the recipients of the 2012 TR35, a group of the world’s top young innovators, for his work using sponges to improve and store alternative fuels. As a member of the TR 35, Professor Dincă was profiled in the September/October issue of Technology Review magazine and will be recognized during their Emerging Technologies Conference (TRETC) in October 2012. |
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Phenyl Ring Dynamics in a Tetraphenylethylene-Bridged Metal–Organic Framework: Implications for the Mechanism of Aggregation-Induced Emission
Natalia B. Shustova, Ta-Chung Ong, Anthony F. Cozzolino Vladimir K. Michaelis,
Robert G. Griffin and Mircea Dincă
Molecules that exhibit emission in the solid state, especially those known as aggregation-induced emission (AIE) chromophores, have found applications in areas as varied as light-emitting diodes and biological sensors. Despite numerous studies, the mechanism of fluorescence quenching in AIE chromophores is still not completely understood. To this end, much interest has focused on understanding the low-frequency vibrational dynamics of prototypical systems, such as tetraphenylethylene (TPE), in the hope that such studies would provide more general principles toward the design of new sensors and electronic materials.
We hereby show that a perdeuterated TPE-based metal–organic framework (MOF) serves as an excellent platform for studying the low-energy vibrational modes of AIE-type chromophores. In particular, we use solid-state 2H and 13C NMR experiments to investigate the phenyl ring dynamics of TPE cores that are coordinatively trapped inside a MOF and find a phenyl ring flipping energy barrier of 43(6) kJ/mol. DFT calculations are then used to deconvolute the electronic and steric contributions to this flipping barrier. Finally, we couple the NMR and DFT studies with variable-temperature X-ray diffraction experiments to propose that both the ethylenic C=C bond twist and the torsion of the phenyl rings are important for quenching emission in TPE, but that the former may gate the latter. To conclude, we use these findings to propose a set of design criteria for the development of tunable turn-on porous sensors constructed from AIE-type molecules, particularly as applied to the design of new multifunctional MOFs. |
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Stephen L. Buchwald, Camille Dreyfus Professor of Chemistry has been selected to receive the ACS 2013 Arthur C. Cope Award sponsored by the Arthur C. Cope Fund |
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Timothy M. Swager, John D. MacArthur Professor of Chemistry, has been selected to receive the ACS 2013 Award for Creative Invention sponsored by ACS Corporation Associates. |
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Tangled Up in Knots: Structures of Inactivated Forms of E. coli Class Ia Ribonucleotide Reductase
Christina M. Zimanyi, Nozomi Ando, Edward J. Brignole,
Francisco J. Asturias, JoAnne Stubbe, Catherine L. Drennan.
Structure. 2012. 20: 1374-1383. DOI: 10.1016/j.str.2012.05.009
Ribonucleotide reductases (RNRs) provide the precursors for DNA biosynthesis and repair and are successful targets for anticancer drugs. The class Ia RNR from E. coli is the model system for this class of enzymes and is known to form large α4β4 ring structures in the presence of the negative regulator dATP. In the August issue of Structure, researchers in the Drennan laboratory report the concatenation of two α4β4 rings into an (α4β4)2 megacomplex observed in crystal structures of the E. coli RNR in the presence of dATP or the anti-cancer agent gemcitabine-diphosphate. Data from small-angle X-ray scattering and electron microscopy was used understand the solution conditions that contribute to the concatenation observed in the crystals and present a mechanism for the formation of these unusual structures.
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A team of researchers led by Keith Nelson (MIT Professor of Chemistry) and Richard Averitt (BU Professor of Physics) has recently published a paper in the journal Nature demonstrating the first use of high-field terahertz (THz) pulses to induce the insulator-to-metal phase transition in the correlated material, vanadium dioxide (VO2). THz radiation lies between the microwave and infrared regions of the electromagnetic spectrum. The paper describes the novel use of antenna-like structures called split-ring resonators to enhance the THz electric field strength within micron-sized regions. At sufficiently large THz fields, the phase transition occurs through the liberation of electrons that are normally localized on the vanadium atoms of the VO2 lattice. The technique opens up new possibilities for THz field control over phase transitions in many materials including ferroelectrics, superconductors, and magneto-resistive systems. Furthermore, the new experimental platform offers access to THz field strengths large enough to directly move atoms (and not just electrons) far enough from their initial positions in a crystal lattice that collective structural changes can occur. This will enable new insights into the physics of materials moving far from equilibrium along pathways that lead to new structures. The large THz-induced conductivity changes demonstrated in the present work show promise for use in THz and infrared detection and imaging schemes as well, which are currently under development in the MIT and BU labs. |
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| Kebin Fan (image) and Mengkun Liu/Mario D'Amato (eds). |
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Researchers explain how dye-based nanotubes can help harvest light’s energy.
Tiny cylinders help reveal how natural-light-harvesting antennae collect light with exceptional efficiency.
Companies that make commercial solar cells are happy if they can achieve 20 percent efficiency when converting sunlight to electricity; an improvement of even 1 percent is seen as major progress. Go to MIT News |
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Professor Emeritus Jeffrey I. Steinfeld has been selected as a member of the distinguished 2012 class of Fellows of the American Chemical Society.
The new fellows will be honored at the society’s fall national meeting in Philadelphia in August 2012, in a ceremony hosted by ACS Immediate Past-President Nancy B. Jackson.
“ACS is especially proud to honor these chemists, who have given so much to the community and the profession,” said Jackson in announcing the 2012 class of ACS Fellows. “They are leaders whose work is having a lasting beneficial impact, not just on science but also on the ACS community.” |
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Lippard Lab: New drug candidate shows promise against cancer
Platinum compound may offer an alternative to cisplatin, a widely used chemotherapy agent.
Drugs containing platinum are among the most powerful and widely used cancer drugs. However, such drugs have toxic side effects, and cancer cells can eventually become resistant to them.
MIT chemistry professor Stephen J. Lippard, who has spent much of his career studying platinum drugs, has now identified a compound that kills cancer cells better than cisplatin, the most commonly used platinum anticancer drug. The new compound may be able to evade cancer-cell resistance to conventional platinum compounds. Go to MIT News Office to read full article.
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Richard R. Schrock, the Frederick G. Keyes Professor of Chemistry, is pictured with group members: Dr. Alejandro G. Lichtscheidl and Dr. Margaret M. Flook.
Click here to view Slideshow! |
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Van Voorhis Lab: Van Voorhis Lab: A multidisciplinary team of researchers at MIT and in Spain has found a new mathematical approach to simulating the electronic behavior of noncrystalline materials, which may eventually play an important part in new devices including solar cells, organic LED lights and printable, flexible electronic circuits. A multidisciplinary team of researchers at MIT and in Spain has found a new mathematical approach to simulating the electronic behavior of noncrystalline materials, which may eventually play an important part in new devices including solar cells, organic LED lights and printable, flexible electronic circuits. Go to MIT News |
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The students in Catherine Drennan’s chemistry classes are silent with attention when she says the word “energy.” They listen more intensely when she couples energy with the environment and pollution. Click here to read full article in Spectrvm |
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Swager Lab: Comparing apples and oranges
New sensor can accurately measure fruits’ ripeness, helping prevent loss of produce from spoilage. Every year, U.S. supermarkets lose roughly 10 percent of their fruits and vegetables to spoilage, according to the Department of Agriculture. >> |
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Dr. Matt Shoulders, currently an American Cancer Society Postdoctoral Fellow at the Scripps Research Institute in Professor Jeff Kelly’s laboratory, will join the faculty on July 15, 2012. Dr. Shoulders carried out his PhD studies under Professor Ronald T. Raines at the University of Wisconsin-Madison. He received a B.S. in chemistry from Virginia Tech in 2004.
Dr. Shoulders' current research interests involve understanding at a fundamental level how the cell remodels itself to address challenges to protein homeostasis, elucidating the pathophysiology of protein folding-related diseases with poorly defined etiology, and targeting the biological processes uncovered for the development of first-in-class small molecule drugs. |
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In a new paper in Angewandte Chemie, Chayasith Uttamapinant in the Ting Lab shows that azides capable of copper chelation (e.g., picolyl azide) undergo much faster click reactions (CuAAC) than nonchelating azides under a variety of biocompatible conditions.This kinetic enhancement allows site-specific protein labeling to be performed on the surface of living cells with only 10–40 μm CuI/CuII (see scheme). Detection sensitivity was also increased for CuAAC detection of alkyne-modified proteins and RNA. To read the paper click here |
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The Awards Committee of the Royal Society of Chemistry’s (RSC) Organic Division has selected Professor Timothy F. Jamison for the 2012 RSC Merck Award. Professor Jamison was selected for his creative contributions to reaction development and natural-product synthesis, including pioneering work on cascade cyclizations, nickel-catalyzed carbon–carbon bond-forming processes, and flow chemistry. |
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Robert G. Griffin, Professor of Chemistry and Director of the Francis Bitter Magnet Laboratory, has been elected to the American Academy of Arts and Sciences. >> |
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ESSIGMANN APPOINTED AS NEW DIRECTOR OF CEHS
John Essigmann, William R and Betsy P. Leitch Professor in Residence and a Professor in the Departments of Chemistry and Biological Engineering, is the next Director of the Center for Environmental Health Sciences (CEHS), effective April 1, 2012. Professor Essigmann is a long service and highly regarded faculty member in CEHS whose research is at the interface of chemistry, biology and public health, specializing on the mechanisms by which cells respond to DNA damage. Using synthetic methods, novel DNA damage products are prepared and then cloned into genomes of viruses. Following replication of the damaged viruses in cells, he is able to determine if the lesions studied will be mutagenic or toxic to the host. Over a hundred DNA lesions of relevance to environmental toxicology or drug development have been characterized in this system. He is on the editorial boards of six journals and had more than180 research publications, patents and books dealing with nucleic acid damage, repair, mutation and evolution. He serves on the advisory boards of six private companies and more than a dozen academic departments and centers. He is the co-founder and Scientific Advisory Board member of Koronis Pharmaceuticals. Professor Essigmann has stepped down as Associate Department Head of the Department of Chemistry, a position he held from July 1, 2010. In announcing his resignation to take up the CES appointment Sylvia Ceyer, Department Head of Chemistry, acknowledged the department's appreciation for his hard work, wise counsel and dedication to the department. |
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The MIT Energy Initiative has awarded Professor Mircea Dincă seed funding for his energy research in Designer Microporous Materials for Water Desalination and Adsorption Heat Pumps.
MITEI, established in September 2006, is an Institute-wide initiative designed to help transform the global energy system to meet the needs of the future and to help build a bridge to that future by improving today's energy systems. |
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Swager group: Proteases are over-expressed in most cancers and proteolytic activity has been shown to be a viable marker for cancer imaging in vivo. The Swager group has developed a new method for detecting proteases based upon organic nanoparticles (a). The nanoparticles are structurally complex and are formed from the assembly of penta-block copolymers, which have a organic semiconducting luminescent core, a hydrophilic outer shell for water solubility, and a reactive segment for crosslinking with peptides (a). The particles are effectively compressed by the crosslinked peptide network (c) and the particles are quenched with a low luminescence. Cleavage of the peptides effectively relieves the strain and allows the particles to expand and an an increase in luminescence is observed (b). |
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Tokmakoff Lab: Faster way to probe proteins
Infrared spectroscopy allows scientists to analyze protein structure on an ultrafast timescale. more>> |
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2012 Barry M. Goldwater Scholar
P. Bryan Changala is a junior majoring in chemistry and physics who plans to pursue a PhD in physical chemistry, in order to carry out research in molecular spectroscopy and teach physical chemistry at the university level. Bryan has been carrying out research in the Field Group since his freshman year at MIT, studying small molecule gas-phase spectroscopy.
The Barry M. Goldwater Scholarship and Excellence in Education Program was established by Congress in 1986 to honor Senator Barry M. Goldwater, who served his country for 56 years as a soldier and statesman, including 30 years of service in the U.S. Senate. The purpose of the Goldwater Foundation is to provide a continuing source of highly qualified scientists, mathematicians, and engineers by awarding scholarships to college students who intend to pursue careers in these fields. |
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NELSON RECEIVES LIPPINCOTT AWARD
Professor Keith A. Nelson is the 2012 recipient of the Ellis R. Lippincott Award in Vibrational Spectroscopy from the Optical Society of America.Nelson receives the award for his innovations in the development of impulsive stimulated Raman scattering and its applications to the ultrafast vibrational spectroscopy of phonons and intermolecular liquid dynamics. This award was established in 1975 by OSA, the Coblentz Society and the Society for Applied Spectroscopy to honor the unique contributions of Ellis R. Lippincott to the field of vibrational spectroscopy. It is presented to an individual who has made significant contributions to vibrational spectroscopy as judged by his or her influence on other scientists.
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Lippard to be recognized with Sacconi Medal
The Inorganic Chemistry Division of the Italian Chemical Society together with the Luigi Sacconi Foundation, on the occasion of the annual meeting of the Division, awards the Luigi Sacconi Medal to a scientist (Italian or foreigner) who has obtained particularly significant results in Inorganic Chemistry, the field in which Luigi Sacconi gave outstanding contributions. An interesting biography of Professor Sacconi can be read here.
Stephen J. Lipppard, Arthur Amos Noyes Professor of Chemistry, will be honored with the Luigi Sacconi Medal for his outstanding work on cis-Pt and the mechanism of its action. The award ceremony will take place at the annual meeting of the Division in Florence in June 2012. |
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Nicolas Boyer of the Movassaghi group has developed a concise and stereoselective Friedel–Crafts-based strategy to provide an efficient multigram-scale access to the C3-(3'-indolyl)hexahydropyrroloindole substructure, a molecular foundation present in a significant subset of epipolythiodiketopiperazine natural alkaloids.The first-generation solution to (+)-gliocladin B involved the stereoselective formation of (+)-12-deoxybionectin A, a plausible biosynthetic precursor. The synthesis clarified the C15 stereochemistry of (+)-gliocladin B and allowed its full structure confirmation. Further studies of a versatile dihydroxylated diketopiperazine provided a concise and efficient synthesis of (+)-gliocladin B as well as access to (+)-gliocladin C. |
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Freeing radicals from their negative connotations
Killian Award recipient JoAnne Stubbe says some free radicals can be good for you.
For biochemist JoAnne Stubbe, “radical” is a word with many associations.
In the late 1960s, Stubbe was a graduate student at the University of California at Berkeley, where student demonstrators picketed against the Vietnam War. She recalls that at the time, radicals were seen as protestors who were “highly reactive, that one had difficulty controlling and that wreaked havoc on everything they interacted with.” more>> |
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Visualising molecular juggling within a B12-dependent methyltransferase complex
Kung, Y., Ando, N., Doukov, T.I., Blasiak, L.C., Bender, G., Seravalli, J., Ragsdale, S.W., and Drennan, C.L.
Nature AOP March 14, 2012 DOI: 10.1038/nature10916
Methylation chemistry is ubiquitous and vital for cellular functions, from transcriptional regulation in humans to the ability of acetogens to live on carbon dioxide. This week in Nature, the Drennan laboratory in collaboration with the Ragsdale laboratory at the University of Michigan present the long-awaited X-ray structure of all protein components required for the methyl transfer from folic acid (vitamin B9) to cobalamin (vitamin B12), a reaction necessary for maintaining pools of methyl donor S-adenosylmethionine as well for acetogenesis.They find that the methyl transfer between these B vitamins requires a large conformational change that appears to be promoted by folate binding. Amazingly, this dramatic conformational change occurs in the crystal, as in crystallo spectroscopic data demonstrate enzymatic turnover that requires unprecedented movements within a crystal lattice.
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Designer Interfaces for High Efficiency Organic Solar Cells
Graduate Student Jose Lobez and Postdoctorate Trisha Andrew (PhD MIT 2011) working with Professors Swager (MIT Chemistry) and Bulovic (MIT EECS) have demonstrated a general method for the design of organic solar cells with greater than 30% increases in power conversion efficiencies (PCEs).
Small quantities of designer materials assemble at interfaces wherein the charge carriers in organic photovoltaics are formed and prevent recombination events that are presently a factor limiting the efficiency of organic solar cells. |
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| Twelve members of the MIT Corporation and 10 faculty members, including chemistry professor Timothy M. Swager, have been named to a Presidential Search Committee tasked with identifying a successor to President Susan Hockfield.
Additionally, three undergraduate and three graduate students have been named to a Student Advisory Committee that will assist in the search.
On Feb. 16, Hockfield announced her intention to step down as president following more than seven years of service. She will remain as president until a successor takes office.
“I am pleased that we have quickly formed this Presidential Search Committee and that we are moving ahead with this search,” says John S. Reed ’61, SM ’65, chairman of the MIT Corporation. “We have gathered an impressive and insightful team of individuals — with diverse opinions, positions and experiences.”
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Professor Alice Y. Ting, Ellen Swallow Richards Chair, has been selected to receive the Vilcek Foundation Prize for Creative Promise in Biomedical Science.
The Vilcek Prize for Creative Promise recognizes foreign-born artists and scientists who have demonstrated exceptional creativity and originality in the early stages of their careers. Two $25,000 prizes, one in the field of biomedical science and one in a category of the arts or humanities designated by the Foundation, are awarded each year.
The cash award, accompanied by a certificate of recognition created by designer Stefan Sagmeister, is presented to each winner of the Vilcek Prize for Creative Promise during the Foundation’s annual awards dinner in New York City. The Vilcek Prize for Creative Promise was established to encourage and support the artistic and scientific achievements of young immigrants who often face significant challenges in their early careers, and to increase awareness of the notable contributions made by foreign-born scholars and artists in the United States.
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On Wednesday, February 8, the MIT/Harvard Center for Magnetic Resonance (CMR) took delivery of their second 800 MHz (18.8 Tesla) NMR magnet. The magnet has an 89 mm bore, so that it can easily be used for low temperature, magic angle spinning (MAS) experiments that yield high-resolution spectra of solid samples.It will be used for spectroscopy of a variety of biological samples such as membrane or amyloid proteins, ribosomes, etc.The magnet is shielded and it is the first of its kind to have a low temperature refrigerator so that the helium boil-off rate will be essentially zero. Finally, the system features a superconducting sweep coil that will permit it to be used together with a 527 GHz gyrotron ( a high frequency microwave source) to enhance signal intensities by factors of ~100 via dynamic nuclear polarization (DNP) experiments. |
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Diels-Alder Cycloaddition for Fluorophore Targeting to Specific Proteins inside Living Cells
D. S. Liu, A. Tangpeerachaikul, R. Selvaraj, M. T. Taylor, J. M. Fox, A. Y. Ting
J. Am. Chem. Soc. 2011, Just Accepted Manuscript
DOI: 10.1021/ja209325n The Ting Lab, in collaboration with the Fox Lab at the University of Delaware, recently reported the application of a Diels-Alder cycloaddition between a tetrazine and a trans-cyclooctene for live-cell fluorescence imaging of proteins. This fast and bioorthogonal reaction extends Ting Lab’s PRIME technology, for Probe Incorporation Mediated by Enzymes, to the specific targeting of green and red fluorophores to proteins inside the cell. Previously PRIME was limited to blue, coumarin-type fluorophores because larger molecules cannot be accommodated by the ligase component of this technology. In this new scheme, generic fluorophores are targeted to proteins marked with a functional handle by the ligase, via the cycloaddition reaction. |
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Stephen J. Lippard, Arthur Amos Noyes Professor of Chemistry, has been selected to receive the 2012 Christopher J. Frederickson Prize for Research in the Neurobiology of Zinc. Professor Lippard receives the prize jointly with James O. McNamara, M.D, and the Carl R. Deane Professor at Duke University, with whom he co-authored a paper entitled, “Vesicular Zinc Promotes Presynaptic and Inhibits Postsynaptic Long-Term Potentiation of Mossy Fiber-CA3 Synapse,” in Neuron, Volume 71, Issue 6, 1116-1126, 22 September 2011.
Professors Lippard and McNamara will be presented with their prize by Dr. Frederickson himself at the 3rd International Society for Zinc Biology Conference in Melbourne, Australia in January 2012. The executive committee of the IZSB honors Dr. Frederickson for his lifetime research in the field of zinc neurobiology, and his seminal contributions to the foundation of the field. |
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Searching for DNA lesions: Structural evidence for lower and higher-affinity DNA binding conformations of human alkyladenine DNA glycosylase (AAG)
Jeremy W. Setser, Gondichatnahalli M. Lingaraju, C. Ainsley Davis, Leona D. Samson, Catherine L. Drennan
Biochemistry
doi: 10.1021/bi201484k
http://pubs.acs.org/doi/abs/10.1021/bi201484k
published online December 13, 2011 To efficiently repair DNA, human alkyladenine DNA glycosylase (AAG) must search the million-fold excess of unmodified DNA bases to find a handful of DNA lesions. Such a search can be facilitated by the ability of glycosylases, like AAG, to interact with DNA using two affinities: a lower-affinity interaction in a searching process, and a higher-affinity interaction for catalytic repair. The Drennan Lab, in collaboration with the lab of Prof. Leona Samson in Biological Engineering, has solved a crystal structure of this human DNA repair protein that allows us to investigate, for the first time, a lower-affinity depiction of this enzyme. By combining this new insight with existing biochemical and structural data, we are able to consider the big picture question of how DNA binding proteins find their binding sites in the vast expanse of the genome. |
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Imaging Protein-Protein Interactions inside Living Cells via Interaction-Dependent Fluorophore Ligation.
Slavoff SA, Liu DS, Cohen JD, Ting AY.
J Am Chem Soc. 2011;133(49):19769-76.
The Ting Lab recently developed ID-PRIME, or Interaction-Dependent PRobe Incorporation Mediated by Enzymes, a new imaging-based reporter of protein-protein interactions in living cells. The coumarin ligase enzyme LplA is fused to a protein of interest, and LplA′s peptide substrate, LAP, is fused to its interaction partner. Only if the proteins interact do LplA and LAP associate, resulting in coumarin labeling and blue cellular fluorescence. The system is engineered to provide low background in the absence of an interaction and has advantages over existing methods including a short labeling time. |
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Sharpening the Lines
New advance could lead to even smaller features in the constant quest for more compact, faster microchips. Trisha Andrew (PhD '10 Swager Group) and postdoc in RLE is a co-author of a paper that describes a way of creating finer lines on chips. >> |
A glow of recognition
New detectors developed at MIT could provide easy visual identification of toxins or pathogens. The Dincă Lab has developed a new way of revealing the presence of specific chemicals — whether toxins, disease markers, pathogens or explosives. The system visually signals the presence of a target chemical by emitting a fluorescent glow.>> |
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Hamill, M.J., Jost, M., Wong, C.,
Elliott, S.J., and Drennan, C.L.
Flavin-Induced Oligomerization in Escherichia
coli Adaptive Response Protein AidB.
Biochemistry, 2011, 50 (46), pp 10159-10169
The process known as "adaptive response" allows Escherichia coli to survive stress induced by a class of highly mutagenic compounds called DNA alkylating agents. Four proteins are upregulated during the adaptive response, including the flavin-binding protein AidB, the function of which is still largely unknown. In a recent study, the groups of Professor Cathy Drennan at MIT and Professor Sean Elliott at Boston University report the biophysical- characterization of AidB.
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| Using a wide spectrum of techniques including fluorescence anisotropy, analytical ultra-centrifugation, and X-ray crystallography, the researchers demonstrate that AidB undergoes an interesting
flavin-dependent transition in oligomerization state. These results provide strong evidence that flavin plays a structural role in the formation of an AidB tetramer, with potential functional implications. |
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Despite the large interchromophore distances imposed by coordination to metal ions, a carboxylate analogue of tetraphenylethylene anchored by Zn2+ and Cd2+ ions inside MOFs shows fluorescence lifetimes in line with those of close-packed molecular aggregates. Turn-on fluorescence by coordinative ligation in a porous matrix is a powerful approach that may lead to new materials made from chromophores with molecular rotors. The potential utility of MCIE toward building new sensing materials is demonstrated by tuning the fluorescence response of the porous MOFs as a function of adsorbed small analytes. |
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Photo: Dominick Reuter
Nocera Lab: The 'artificial leaf,' a device that can harness sunlight to split water into hydrogen and oxygen without needing any external connections, is seen with some real leaves, which also convert the energy of sunlight directly into storable chemical form.
Go to MIT News Office>>
The Artificial Leaf has been listed as one of the top innovations in
the world by TIME Magazine. |
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H. Gobind Khorana, MIT’s Alfred P. Sloan Professor of Biology and Chemistry emeritus, died of natural causes in Concord, Mass., Wednesday morning. He was 89.
A winner of the 1968 Nobel Prize in physiology or medicine, Khorana devoted much of his scientific career to unraveling the genetic code and the mechanisms by which nucleic acids give rise to proteins. >> |
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Graphic: Christine Daniloff |
Making a Nobel-winning chemistry reaction
even better
Schrock Group: New catalyst offers greater control over the synthesis of organic cyclic compounds, including potential cancer drugs.>> |
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The McNamara group from Duke University and the Lippard group have reported a rapid extracellular chelator for mobile zinc, named ZX1. Its fast zinc-binding kinetics helped researchers to define mobile zinc's role in both presynaptic and postsynaptic mossy fiber long-term potentiation in the brain. Their studies were published in the September 22 issue of Neuron.
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Robert Silbey, Class of 1942 Professor of Chemistry and former MIT dean of science, dies at 71. Silbey was known for his leadership and political acumen as dean, his commitment to enhancing MIT’s education and research, and his work in condensed phase theory and quantum biology, fields that he helped to pioneer. >> |
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Earle K. Plyler Prize for Molecular Spectroscopy
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| The Field group recently observed a new cis-bent isomer of the first singlet electronically excited state of acetylene, reported in Merer et al., J. Chem. Phys. 134 (24), 244310 (2011). This work represents the first high resolution spectroscopic study of cis-trans isomerization in an electronically excited state. Analysis of the unusual spectra was aided by theoretical calculations in Baraban et al., J. Chem. Phys. 134 (24), 244311 (2011). |
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