Chemistry
Researchers in the McCafferty Lab have recently designed a mutant enzyme that shows promise as a molecular probe. This engineered enzyme is a mutant of lysine–specific demethylase 1A (KDM1A/LSD1), an epigenetic target with therapeutic potential. The researchers removed a protein interaction domain from KDM1A and replaced it with the corresponding region of a closely related enzyme. This molecular tool will allow users to effectively study the protein–protein interactions of KDM1A. Read more here. read more about Uncoupling Protein–Protein Interactions from Enzyme Catalysis »
Duke chemists have used single molecule techniques to induce forbidden reactions and probe the structures of the associated transition states. Read more here. read more about A Glimpse Of The Forbidden »
Patrick Charbonneau hosts seminar in Paris to relate his experience teaching an introductory-level science class on melding chemistry and cuisine at Duke University. Contemporary chefs such as Ferran Adrià, Joan Roca, and Heston Blumenthal have more than fame in common. They use soft matter chemistry and physics to create a gastronomy that challenges the traditional culinary experience. Techniques are not followed blindly, they are deconstructed, explained, and brought to new heights. View the seminar, hosted… read more about Charbonneau presents Soft matter and cooking: a pedagogical experience in Paris »
A Physics Today article describes new experiments that are testing predictions of Professor David Beratan's group on how infra-red radiation may be used to gate charge flow through molecules. The recent experiment are testing Beratan's ideas of how vibrational excitation may be used to modulate electronic coupling "pathways" and their quantum mechanical interferences in molecules. The writeup appears here read more about Toward a Molecular "Double-slit" Experiment »
A paper by Chetan Rupakheti and Aaron Virship, in collaboration with Professors Yang and Beratan, reports a new approach to develop property-biased molecular libraries that capture the diversity of vast "molecular space." The paper was selected as an Editors' Choice in the /Journal of Chemical Information and Modeling/ and is available as a "just accepted" manuscript at: http://pubs.acs.org/doi/abs/10.1021/ci500749q. read more about New Approach Creates Property-Biased Molecular Libraries in silico »
The Widenhoefer group has recently reported the synthesis and structure of the first gold carbene complex lacking heteroatom stabilization. Unstabilzied gold carbene complexes have been widely invoked as reactive intermediates in gold- catalyzed transformations but have heretofore escaped direct detection and characterization. This work, co-authored with graduate student Robert Harris, recently appeared in Angewandte Chemie. The article may be found here, citing Harris, R. J.; Widehoefer, R… read more about Gold Carbene Complex Lacking Heteroatom Stabilization »
Dr Agostino Migliore and collaborators are taking a major step forward in understanding the basic rules of charge transport through long polymer wires and in their implementation in more complex electrical circuits. Their work recently appeared in Nature Nanotechnology and is a result of an international collaboration led by the experimental group of Prof. Danny Porath (from The Hebrew University of Jerusalem) and involving experimentalists and theorists from Israel, USA, and Europe. The experiments in… read more about Migliore and Collaborators re-ignite interest in DNA-based wires »
Professor Derbyshire is the lead author on a new study that identifies several kinase inhibitors that show promise as anti-malarial drugs. The work, which was recently published online in ChemBioChem, was also highlighted in the August 25, 2014 article in Duke Today and in the October 2, 2014 article in Duke Today. read more about Professor Derbyshire and Colleagues Find New Ways to Fight Malaria »
Members of the Franz lab joined forces with collaborators in the Duke University Medical School to show that a small molecule enhances antifungal activity by taking advantage of chemical processes induced by the immune system. The molecule, nicknamed QBP, transforms from a non-toxic compound to a lethal agent upon interacting with reactive oxygen species and copper, both of which are released by activated immune cells. The toxic agent overrides the copper detoxification machinery in microbial pathogens in a way that… read more about Franz Group Develops a Strategy to Recruit Copper to Kill Pathogens »
The Fitzgerald Group recently described the development and application of two new experimental protocols that significantly expand the scope of their SPROX methodology for the large-scale and high-throughput analysis of protein-ligand binding interactions on the proteomic scale. The work is reported in two recently published papers, one in Analytical Chemistry that is co-authored by graduate student researchers Yingrong Xu and Erin Strickland and the other in Molecular and Cellular Proteomics … read more about Fitzgerald Group Advances Protein-Ligand Binding Methodology »
The Crumbliss group in collaboration with microbiology and bioinformatics groups at the University of Minnesota and Chatham University have shown that the periplasmic iron transport protein FbpABp from the causative agent of whooping cough, Bordetella pertussis, selectively binds both unchelated Fe(III), and native and xeno Fe(III) siderophore complexes. These data support the existence of a continuum between periplasmic binding proteins (PBP) and bacterial transferrins and represents a new paradigm for iron… read more about The Crumbliss Group Identifies a New Paradigm for Iron Transport In Gram Negative Bacteria »
A new theory for charge transport indicates that multiple redox species in close contact can "find" states with nearly matched energy levels, permitting ballistic-like transport during the lifetime of the energy-matched states. The theory predicts charge transfer rates that decay exponentially with distance, thus presenting a signature that is easily mistaken for quantum mechanical tunneling. This new mechanism may help to explain charge flow in damaged DNA and in bacterial redox-active nanowires,… read more about Beratan's group develops a theory for "flickering resonance" charge transfer »
Charbonneau and colleagues incorporate the jamming transitions of granular materials into glass theory. More details can be found in their recentNature Communications and on Duke Today. read more about The Charbonneau group helps identify a new type of criticality near jamming. »
The Therien and Beratan groups have published a comprehensive review on the "Biochemistry and Theory of Proton Coupled Electron Transfer Reactions," in a collaborative project led by Agostino Migliore and Nicholas Polizzi. The paper appears in a thematic issue of Chemical Reviews focused on Bioinorganic Enzymology. read more about Biochemistry and Theory of Proton Coupled Electron Transfer Reactions »
Graduate student Kyle Daniels (Oas lab) has determined a complex protein folding mechanism. This study which was recently published in The Journal of the American Chemical Society, employed stopped-flow fluorescence data, x-ray crystallography and isothermal titration calorimetry to deduce the equilibrium flux through 18 possible pathways in the coupled folding and pyrophosphate binding reaction of RNase P protein. The work involved the collaboration of three other groups whose expertise… read more about Mechanism of Coupled Protein Folding and Ligand Binding Through Multiple Pathways »
Duke researchers, with collaborators from the NC Museum of Art in Raleigh and the National Gallery of Art in Washington, DC, demonstrate the imaging capabilities of femtosecond pump-probe microscopy to reveal the layering structures of pigments in historically relevant paintings. In work recently reported in PNAS the Warren group successfully used the femtosecond pump-probe microscopy technique to noninvasively image the paint pigments in a 14th century painting, The Crucifixion by Puccio… read more about Warren group pioneers use of laser microscopy in art history and conservation »
The Liu group recently published their new finding of "winged nanotubes" in Scientific Reports, the newest member of the Nature family. The new types of nanotube, composed of a nanotube core and graphene wings, combine the advantages of nanotube and graphene while overcoming the limitations of the individual components, as discussed in detail in the paper. These new structures were shown to exhibit outstanding activity toward catalyzing the oxygen reduction reaction (ORR), with excellent stability and methanol/carbon… read more about Winged Nanotubes Show Promise in Electrocatalysis »
Recently reported in Angewandte Chemie, the Chilkoti and McCafferty groups at Duke have collaborated to discover a "three-in-one" facile method for the chromatography-free purification of recombinant proteins and optional, site-specific conjugation of the protein to a small moleule. The investigators have prepared a first-in-class recombinant expression and purification system that combines elastin-like polypeptide sequences (ELPs), which transition between soluble and insoluble phases with changes in temperature, with… read more about Three-in-One Chromatography-Free Purification, Tag Removal, and Site-Specific Modification of Recombinant Fusion Proteins Using Sortase A and Elastin-like Polypeptides »
Solar-driven water splitting with photoelectrochemical cells is an attractive means to convert intermittent solar radiation into H2 for use as a storable, non-polluting fuel. However, photoelectrochemical cells often rely on a costly, fragile and electrochemically unstable material, indium tin oxide (ITO), as the transparent electrode. In addition, the water splitting catalyst deposited on ITO can obstruct the transmission of light to the dye or photovoltaic component. To address these limitations, the Wiley lab has… read more about The Wiley Lab Makes Optically Transparent Water Oxidation Catalyst from Copper Nanowires »
How does nature handle copper, an essential metal that is also potentially toxic? To find out, check out this Franz lab review article, which was featured on the February cover of the Journal of Inorganic Biochemistry. read more about The Franz Lab Reviews Nature's Ability to Handle Copper »
The Hong lab has recently reported the total synthesis of (+)-dactylolide in 19 steps for the longest sequence from commercially available 1,3-dithiane with an overall yield of 1.4%. The total synthesis of (+)-dactylolide was accomplished through the 1,6-oxa conjugate addition reaction of a 2,4-dienal for the facile synthesis of the 2,6-cis-2-(4-oxo-2-butenyl)-tetrahydropyran subunit, the umpolung alkylation reaction of a cyanohydrin, and the NHC-catalyzed oxidative macrolactonization reaction for the synthesis of the 20-… read more about The Hong Lab Reports the Synthesis of (+)-dactylolide in 19 Steps »
The Widenhoefer group has recently reported the gold(I)-catalyzed stereoconvergent, intermolecular enantioselective hydroamination of chiral, racemic 1,3-disubstituted allenes, which represents the first example of enantioselective intermolecular allene hydroamination. The method effectively forms N-allylic carbamates, which are important chiral building blocks, with high regio- and diastereoselectivity and with up to 92% ee. The editors of Angewandte Chemie have designated it a “hot paper”. Butler, K. L.; Tragni, M.;… read more about The Widenhoefer Group Reports the First Example of Enantioselective Intermolecular Allene Hydroamination »
How do ionic interactions and macromolecules play a role in iron transport in living cells? Find out by reading the chapter from the Crumbliss lab “Iron Transport in Living Cells” by A. L. Crumbliss and C. J. Parker Siburt, which was featured on the cover of the monograph Ionic Interactions in Natural and Synthetic Macromolecules (Wiley, 2012), edited by Visiting Professor of Chemistry Alberto Ciferri and Angelo Perico. read more about The Crumbliss Lab on Ionic Interactions and Macromolecules' Role in Iron Transport in Living Cells »
Graduate student Nick Polizzi and collaborators in Beratan's lab have built a theoretical model to describe how charge flows through bacterial appendages, known as pili. Pili are implicated in the exchange of electrons between living organisms and inorganic substrates. These studies may assist in the design of future semi-biological solar cells that would convert sunlight into liquid fuels, with the help of photovoltaics that are "plugged" into living bacteria. Details appear in: Faraday Discussions, 155, 43-62 (2012). read more about Theoretical Model Describes Charge Flows through Pili »
Recent work from the Craig lab reports a functional group that grows longer in response to applied machincal forces, a response that can subsequently be reversed by shining light on the sample. Read more about the new mechanophore and its properties here. read more about Functional Group Lengthens in Response to Applied Mechanical Forces »
The Charbonneau group has recently taken a crack at the glass problem. Read more in Charbonneau et al., Phys. Rev. Lett. 107 185702 (2011); 108, 035701 (2012) read more about Charbonneau Group Takes a Crack at the Glass Problem »