Chemistry
Showing 101-150 of 330 Results
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Keith Hodgson
David Mulvane Ehrsam and Edward Curtis Franklin Professor of Chemistry and Professor of Photon Science
BioCombining inorganic, biophysical and structural chemistry, Professor Keith Hodgson investigates how structure at molecular and macromolecular levels relates to function. Studies in the Hodgson lab have pioneered the use of synchrotron x-radiation to probe the electronic and structural environment of biomolecules. Recent efforts focus on the applications of x-ray diffraction, scattering and absorption spectroscopy to examine metalloproteins that are important in Earth’s biosphere, such as those that convert nitrogen to ammonia or methane to methanol.
Keith O. Hodgson was born in Virginia in 1947. He studied chemistry at the University of Virginia (B.S. 1969) and University of California, Berkeley (Ph.D. 1972), with a postdoctoral year at the ETH in Zurich. He joined the Stanford Chemistry Department faculty in 1973, starting up a program of fundamental research into the use of x-rays to study chemical and biological structure that made use of the unique capabilities of the Stanford Synchrotron Radiation Lightsource (SSRL). His lab carried out pioneering x-ray absorption and x-ray crystallographic studies of proteins, laying the foundation for a new field now in broad use worldwide. In the early eighties, he began development of one of the world's first synchrotron-based structural molecular biology research and user programs, centered at SSRL. He served as SSRL Director from 1998 to 2005, and SLAC National Accelerator Laboratory (SLAC) Deputy Director (2005-2007) and Associate Laboratory Director for Photon Science (2007-2011).
Today the Hodgson research group investigates how molecular structure at different organizational levels relates to biological and chemical function, using a variety of x-ray absorption, diffraction and scattering techniques. Typical of these molecular structural studies are investigations of metal ions as active sites of biomolecules. His research group develops and utilizes techniques such as x-ray absorption and emission spectroscopy (XAS and XES) to study the electronic and metrical details of a given metal ion in the biomolecule under a variety of natural conditions.
A major area of focus over many years, the active site of the enzyme nitrogenase is responsible for conversion of atmospheric di-nitrogen to ammonia. Using XAS studies at the S, Fe and Mo edge, the Hodgson group has worked to understand the electronic structure as a function of redox in this cluster. They have developed new methods to study long distances in the cluster within and outside the protein. Studies are ongoing to learn how this cluster functions during catalysis and interacts with substrates and inhibitors. Other components of the protein are also under active study.
Additional projects include the study of iron in dioxygen activation and oxidation within the binuclear iron-containing enzyme methane monooxygenase and in cytochrome oxidase. Lab members are also investigating the role of copper in electron transport and in dioxygen activation. Other studies include the electronic structure of iron-sulfur clusters in models and enzymes.
The research group is also focusing on using the next generation of x-ray light sources, the free electron laser. Such a light source, called the LCLS, is also located at SLAC. They are also developing new approaches using x-ray free electron laser radiation to image noncrystalline biomolecules and study chemical reactivity on ultrafast time scales. -
Wray Huestis
Professor of Chemistry, Emerita
BioProfessor Wray Huestis’ research concerns the molecular mechanisms whereby cells control their shape, motility, deformability and the structural integrity of their membranes. Metabolic control of interprotein and protein-lipid interactions is studied by a variety of biochemical, spectroscopic and radiochemical techniques, including fluorescence and EPR spectrometry, autoradiography and electron microscopy. The role of lipid metabolism and transport in regulating the fluid dynamics of cell suspensions (red blood cells, platelets, lymphocytes) is examined using circulating cells and cells grown in culture. Cell-cell and cell-liposome interactions are studied using model membrane systems with widely differing physical properties. Complexes of liposomes and encapsulated viruses are used as selective vectors to deliver water-soluble compounds across the membranes of intact cells. The particular projects described in the listed publications have as a common goal an understanding of the molecular workings of the cell membrane.
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Matthew Kanan
Professor of Chemistry and Senior Fellow at the Precourt Institute for Energy
BioMatt Kanan is a Professor of Chemistry and Director of the TomKat Center for Sustainable Energy at Stanford. Matt’s research group addresses challenges in energy conversion, sustainable resource utilization, and carbon dioxide removal. Their work has led to several inventions in these areas, including process technology that utilizes CO2 to streamline chemical production, metal-free CO2 hydrogenation catalysts that improve the efficiency of sustainable fuel synthesis, membrane-free electrochemical systems to generate acid and base from water, and thermochemical methods to activate silicate rocks for CO2 removal. Matt is the co-founder and Chief Scientific Advisor for ReSource Chemical Corp., an Oakland-based start-up commercializing a process created in his group to produce performance-advantaged plastics from CO2 and inedible biomass. At the TomKat Center, Matt directs programs that help Stanford students and researchers develop and commercialize innovations that impact energy and sustainability. Prior to joining the Stanford faculty in 2009, Matt did his Ph.D. studies in organic chemistry at Harvard and postdoctoral research at MIT in inorganic chemistry. He earned his B.A. in chemistry from Rice University in 2000.
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Hemamala Karunadasa
J.G. Jackson and C.J. Wood Professor of Chemistry and Senior Fellow at the Precourt Institute for Energy
BioProfessor Hema Karunadasa works with colleagues in materials science, earth science, and applied physics to drive the discovery of new materials with applications in clean energy. Using the tools of synthetic chemistry, her group designs materials that couple the structural tunability of organic molecules with the diverse electronic and optical properties of extended inorganic solids. This research targets materials such as sorbents for capturing environmental pollutants, phosphors for solid-state lighting, and absorbers for solar cells.
Hemamala Karunadasa studied chemistry and materials science at Princeton University (A.B. with high honors 2003; Certificate in Materials Science and Engineering 2003), where her undergraduate thesis project with Professor Robert J. Cava examined geometric magnetic frustration in metal oxides. She moved from solid-state chemistry to solution-state chemistry for her doctoral studies in inorganic chemistry at the University of California, Berkeley (Ph.D. 2009) with Professor Jeffrey R. Long. Her thesis focused on heavy atom building units for magnetic molecules and molecular catalysts for generating hydrogen from water. She continued to study molecular electrocatalysts for water splitting during postdoctoral research with Berkeley Professors Christopher J. Chang and Jeffrey R. Long at the Lawrence Berkeley National Lab. She further explored molecular catalysts for hydrocarbon oxidation as a postdoc at the California Institute of Technology with Professor Harry B. Gray. She joined the Stanford Chemistry Department faculty in September 2012. Her research explores solution-state routes to new solid-state materials.
Professor Karunadasa’s lab at Stanford takes a molecular approach to extended solids. Lab members gain expertise in solution- and solid-state synthetic techniques and structure determination through powder- and single-crystal x-ray diffraction. Lab tools also include a host of spectroscopic and electrochemical probes, imaging methods, and film deposition techniques. Group members further characterize their materials under extreme environments and in operating devices to tune new materials for diverse applications in renewable energy.
Please visit the lab website for more details and recent news. -
Chaitan Khosla
Wells H. Rauser and Harold M. Petiprin Professor and Professor of Chemistry and, by courtesy, of Biochemistry
Current Research and Scholarly InterestsResearch in this laboratory focuses on problems where deep insights into enzymology and metabolism can be harnessed to improve human health.
For the past two decades, we have studied and engineered enzymatic assembly lines called polyketide synthases that catalyze the biosynthesis of structurally complex and medicinally fascinating antibiotics in bacteria. An example of such an assembly line is found in the erythromycin biosynthetic pathway. Our current focus is on understanding the structure and mechanism of this polyketide synthase. At the same time, we are developing methods to decode the vast and growing number of orphan polyketide assembly lines in the sequence databases.
For more than a decade, we have also investigated the pathogenesis of celiac disease, an autoimmune disorder of the small intestine, with the goal of discovering therapies and related management tools for this widespread but overlooked disease. Ongoing efforts focus on understanding the pivotal role of transglutaminase 2 in triggering the inflammatory response to dietary gluten in the celiac intestine. -
Eric Kool
George A. and Hilda M. Daubert Professor of Chemistry
Current Research and Scholarly Interests• Design of cell-permeable reagents for profiling, modifying, and controlling RNAs
• Developing fluorescent probes of DNA repair pathways, with applications in cancer, aging, and neurodegenerative disease
• Discovery and development of small-molecule modulators of DNA repair enzymes, with focus on cancer and inflammation -
Jason Kronenfeld
Ph.D. Student in Chemistry, admitted Autumn 2021
BioJason Kronenfeld holds a Bachelors of Science in Chemistry with minors in French and Math from The University of Arizona (Graduated May 2021, Summa Cum Laude with Honors). Jason spent his time at UArizona conducting research in Benjamin J. Renquist's group and working with Honors students as a Resident Assistant.
He joined the Renquist research group in 2017 where he has worked on projects related to lactation, metabolic rate, hyperinsulinemia and insulin resistance, asthma, and more. He led work on two projects. 1) Understanding the mechanism by which heat suppresses food intake as an effect of global warming. Increasing heat-stressed food intake is proposed to increase milk production in lactating mammals, increase animal efficiency, and decrease milk production costs. 2) Creating a novel approach to address glycemic control for treatment of type two diabetes mellitus – a collaboration with Dr. Khanna's research group to conduct in silico, in vivo, and in vitro testing of the novel approach.
In Fall 2021, Jason entered the Stanford University PhD program in chemistry, to be eventually followed with a post-doctoral fellowship with the ultimate goal of acting as a principal investigator in academia. He performs research in the DeSimone Lab focused on applications of high-resolution continuous liquid interface production (CLIP) under a National Science Foundation Graduate Research Fellowship. Outside of the lab, Jason is involved in research ethics and public communication initiatives as well as a student-led waltz performance group (Stanford Committee on Research, The Civilian, and the Viennese Ball Opening Committee, respectively).