School of Humanities and Sciences

Showing 1-7 of 7 Results

  • Lynette Cegelski

    Lynette Cegelski

    Associate Professor of Chemistry and, by courtesy, of Chemical Engineering

    Current Research and Scholarly InterestsOur research program integrates chemistry, biology, and physics to investigate the assembly and function of macromolecular and whole-cell systems. The genomics and proteomics revolutions have been enormously successful in generating crucial "parts lists" for biological systems. Yet, for many fascinating systems, formidable challenges exist in building complete descriptions of how the parts function and assemble into macromolecular complexes and whole-cell factories. We are inspired by the need for new and unconventional approaches to solve these outstanding problems and to drive the discovery of new therapeutics for human disease.

    Our approach is different from the more conventional protein-structure determinations of structural biology. We employ biophysical and biochemical tools, and are designing new strategies using solid-state NMR spectroscopy to examine assemblies such as amyloid fibers, bacterial cell walls, whole cells, and biofilms. We would like to understand at a molecular and atomic level how bacteria self-assemble extracellular structures, including functional amyloid fibers termed curli, and how bacteria use such building blocks to construct organized biofilm architectures. We also employ a chemical genetics approach to recruit small molecules as tools to interrupt and interrogate the temporal and spatial events during assembly processes and to develop new strategies to prevent and treat infectious diseases. Overall, our approach is multi-pronged and provides training opportunities for students interested in research at the chemistry-biology interface.

  • James K. Chen

    James K. Chen

    Jauch Professor and Professor of Chemical and Systems Biology, of Developmental Biology and of Chemistry

    Current Research and Scholarly InterestsOur laboratory combines chemistry and developmental biology to investigate the molecular events that regulate embryonic patterning, tissue regeneration, and tumorigenesis. We are currently using genetic and small-molecule approaches to study the molecular mechanisms of Hedgehog signaling, and we are developing chemical technologies to perturb and observe the genetic programs that underlie vertebrate development.

  • Christopher Chidsey

    Christopher Chidsey

    Associate Professor of Chemistry, Emeritus

    Current Research and Scholarly InterestsThe Chidsey group research interest is to build the chemical base for molecular electronics. To accomplish this, we synthesize the molecular and nanoscopic systems, build the analytical tools and develop the theoretical understanding with which to study electron transfer between electrodes and among redox species through insulating molecular bridges

  • James Collman

    James Collman

    George A. and Hilda M. Daubert Professor of Chemistry, Emeritus

    BioProfessor Emeritus James Collman has made landmark contributions to inorganic chemistry, metal ion biochemistry, homogeneous catalysis, and transition metal organometallic chemistry. He pioneered numerous now-popular research tools to reveal key structural and functional details of metalloenzymes essential to respiration and energy, and hemoglobin and myoglobin, essential to oxygen transport in the blood.

    Born 1932 in Beatrice, Nebraska, James P. Collman studied chemistry at U. Nebraska–Lincoln (B.S. 1954, M.S. 1956). His doctoral work at U. Illinois at Urbana-Champaign (Ph.D., 1958) focused on Grignard reagents. As a faculty member at U. North Carolina, he demonstrated aromatic reactivity in metal acetylacetonates, and he developed metal complexes that hydrolyze peptide bonds under physiological conditions. He came to Stanford University as Professor of Chemistry in 1967. Among many honors, Prof. Collman’s was elected to the National academy of Sciences in 1975, and named California Scientist of the Year in 1983.

    At Stanford, Prof. Collman invented a new paradigm for studying biological systems using functional synthetic analogs of metal-containing enzyme systems, free from the protein coatings that can affect metalloprotein chemical properties. This strategy allowed him to elucidate the intrinsic reactivity of the metal center as well as the effects of protein-metal interactions on biological function.

    One focal point of this research has involved heme-proteins such as the oxygen (O2) carrier hemoglobin (Hb), and the O2-storing protein myoglobin (Mb). Prof. Collman was the first to prepare and characterize stable, functional analogues of the Hb and Mb active sites, which contain an iron derivative of the large flat “porphyrin” ligand. In his “picket fence” porphyrin, groups installed on the periphery block side reactions, which would otherwise degrade the structure. This protected iron complex manifests the unique magnetic, spectroscopic and structural characteristics of the O2-binding Hb and Mb sites, and exhibits very similar O2-binding affinities.

    The Collman Group also prepared functional mimics of the O2-binding/reducing site in a key respiration enzyme, cytochrome c oxidase, CcO, which converts O2 to H2O during biosynthesis of the energy storage molecule ATP. This enzyme must be very selective: partial O2 reduction products are toxic. Prof. Collman invented a powerful synthetic strategy to create analogs of the CcO active site and applied novel electrochemical techniques to demonstrate that these models catalyze the reduction of O2 to water without producing toxic partially-reduced species. He was able to mimic slow, rate-limiting electron delivery by attaching his CcO model to a liquid-crystalline membrane using “click chemistry.” He demonstrated that hydrogen sulfide molecules and heterocycles reversibly bind to the metal centers at CcO’s active site, connecting a synthetic enzyme model to simple molecules that reversibly inhibit respiration. These respiration inhibitors exhibit physiological properties, affecting blood clotting and controlling the effects of the hormone, nitric oxide, NO.

    In addition, Prof. Collman performed fundamental studies of organometallic reactions. He also prepared and characterized homodinuclear and heterodinuclear complexes having metal-metal multiple bonds, and made the first measurements of the rotational barriers found in multiple metal-metal bonds.

    Prof. Collman’s impactful textbook “Principles and Applications of Organotransition Metal Chemistry” has seen multiple editions. His book “Naturally Dangerous: Surprising Facts About Food, Health, and the Environment” explains the science behind everyday life, and received favorable reviews in Nature and The Washington Post.

  • Bianxiao Cui

    Bianxiao Cui

    Job and Gertrud Tamaki Professor of Chemistry

    Current Research and Scholarly InterestsOur objective is to develop new biophysical methods to advance current understandings of cellular machinery in the complicated environment of living cells. Currently, we are focusing on four research areas: (1) Membrane curvature at the nano-bio interface; (2) Nanoelectrode arrays (NEAs) for scalable intracellular electrophysiology; (3) Electrochromic optical recording (ECORE) for neuroscience; and (4) Optical control of neurotrophin receptor tyrosine kinases.

  • Yi Cui

    Yi Cui

    Director, Precourt Institute for Energy, Professor of Materials Science and Engineering, Senior Fellow at the Woods Institute for the Environment and Professor, by courtesy, of Chemistry

    BioCui studies fundamentals and applications of nanomaterials and develops tools for their understanding. Research Interests: nanotechnology, batteries, electrocatalysis, wearables, 2D materials, environmental technology (water, air, soil), cryogenic electron microscopy.