A5014665367- Biofuel production and bioconversion
- Advanced Cellulose Research Studies
- Lignin and Wood Chemistry
- Catalysis for Biomass Conversion
- Protein Structure and Dynamics
- Spectroscopy and Quantum Chemical Studies
- Polysaccharides and Plant Cell Walls
- Zeolite Catalysis and Synthesis
- Enzyme Production and Characterization
- Enzyme Catalysis and Immobilization
- Hemoglobin structure and function
- Thermochemical Biomass Conversion Processes
- Photosynthetic Processes and Mechanisms
- Microbial Metabolic Engineering and Bioproduction
- Fermentation and Sensory Analysis
- Catalysis and Hydrodesulfurization Studies
- Glycosylation and Glycoproteins Research
- Advanced Combustion Engine Technologies
- Photoreceptor and optogenetics research
- Extraction and Separation Processes
- Advanced NMR Techniques and Applications
- Enzyme Structure and Function
- Particle accelerators and beam dynamics
- Biochemical and biochemical processes
- Plant nutrient uptake and metabolism
National Renewable Energy Laboratory
2015-2024
Institute of Immunology
2024
Colorado School of Mines
2013
National Energy Research Center
2011
Scripps Research Institute
2006-2008
Center for Theoretical Biological Physics
2006-2008
Boston University
2002-2008
Peking University
2001
Plant secondary cell walls (SCWs) are composed of a heterogeneous interplay three major biopolymers: cellulose, hemicelluloses, and lignin. Details regarding specific intermolecular interactions higher-order architecture the SCW superstructure remain ambiguous. Here, we use solid-state nuclear magnetic resonance (ssNMR) measurements to infer refined details about structural configuration, interactions, relative proximity all biopolymers within air-dried
We probe the molecular-level behavior of Family 1 carbohydrate-binding module (CBM) from a commonly studied fungal cellulase, 7 cellobiohydrolase (Cel7A) Trichoderma reesei, on hydrophobic face crystalline cellulose. With fully atomistic model, we predict that CBM alone exhibits regions thermodynamic stability along cellulose chain corresponding to cellobiose unit, which is catalytic product entire Cel7A enzyme. In addition, determine residues and types interactions are responsible for...
Applications and associated processing technologies of lignocellulosic biomass are becoming increasingly important as we endeavor to meet societal demand for fuels, chemicals, materials from renewable resources. Meanwhile, the rapidly expanding availability capabilities high-performance computing present an unprecedented opportunity accelerate development surrounding lignocellulose utilization. In order realize this potential, suitable modeling frameworks must be constructed that effectively...
A multiscale simulation model is used to construct potential and free energy surfaces for the carbohydrate-binding module [CBM] from an industrially important cellulase, Trichoderma reesei cellobiohydrolase I, on hydrophobic face of a coarse-grained cellulose Iβ polymorph. We predict computation that CBM alone exhibits regions stability every 5 10 Å, corresponding glucose unit cellobiose unit, respectively. In addition, we new role CBM: specifically, in presence hydrolyzed chain ends, exerts...
Two-component signal transduction systems with membrane-embedded sensor histidine kinases are believed to recognize environmental signals and transduce this information over the cellular membrane influence activity of a transcription factor which they mated. The YycG kinase Bacillus subtilis, containing two transmembrane helices, is subject complicated activity-control circuit involving other proteins N-terminal YycH YycI. Truncation studies YycI demonstrated that individual helices these...
Understanding the enzymatic mechanism that cellulases employ to degrade cellulose is critical efforts efficiently utilize plant biomass as a sustainable energy resource. A key component of cellulase action on product inhibition from monosaccharide and disaccharides in site tunnel. The absolute binding free cellobiose glucose catalytic tunnel Family 7 cellobiohydrolase (Cel7A) Trichoderma reesei (Hypocrea jecorina) was calculated using two different approaches: steered molecular dynamics...
Microbial conversion of aromatic compounds is an emerging and promising strategy for valorization the plant biopolymer lignin. A critical often rate-limiting reaction in catabolism O -aryl-demethylation abundant methoxy groups lignin to form diols, which enables subsequent oxidative ring-opening. Recently, a cytochrome P450 system, GcoAB, was discovered demethylate guaiacol (2-methoxyphenol), can be produced from coniferyl alcohol-derived lignin, catechol. However, native GcoAB has minimal...
Abstract The ignition, oxidation, and pyrolysis chemistry of methyl propyl ether (MPE) was probed experimentally at several different conditions, a comprehensive chemical kinetic model constructed to help understand the observations, with many key parameters computed using quantum transition state theory. Experiments were carried out in shock tube measuring time variation CO concentrations, flow product rapid compression machine (RCM) ignition delay times. detailed reaction mechanism...
Biological funneling of lignin-derived aromatic compounds is a promising approach for valorizing its catalytic depolymerization products. Industrial processes bioconversion will require efficient enzymes key reactions, including demethylation O-methoxy-aryl groups, an essential and often rate-limiting step. The recently characterized GcoAB cytochrome P450 system comprises coupled monoxygenase (GcoA) reductase (GcoB) that catalyzes oxidative the group in guaiacol. Here, we evaluate series...
Cellobiohydrolases (CBHs) are typically major components of natural enzyme cocktails for biomass degradation. Their active sites enclosed in a tunnel, enabling processive hydrolysis cellulose chains. Glycoside hydrolase Family 6 (GH6) CBHs act from nonreducing ends by an inverting mechanism and present many cellulolytic fungi bacteria. The bacterial Thermobifida fusca Cel6B (TfuCel6B) exhibits longer more site tunnel than its fungal counterparts. Here, we determine the structures two...
Diffusion of biomass pyrolysis vapors and their upgraded products is an essential catalytic property zeolites during fast likely plays a critical role in the selectivity these catalysts. Characterizing diffusivities representative biofuel molecules to understand shape interpret product distribution. Yet, experimental measurements on oxygenated at temperatures are very limited literature. As alternative approach, we conducted MD simulations measure diffusion coefficients several selected that...
The rate and mechanism of the kinetic energy relaxation directly excited heme in cytochrome c was investigated using classical molecular dynamics simulation. found to be a biphasic exponential decay process with time constants 1.5 ps for fast 10.1 slow process. Approximately 60% relaxes on short scale. Energy flow from protein is occur "through bond" via (1) covalent linkages Cys14, Cys17, His18, Met80 residues (2) hydrogen bonds Tyr48, Thr49, Asn52, Thr78 nearby water molecules space"...
Secondary plant cell walls are composed of carbohydrate and lignin polymers, collectively represent a significant renewable resource. Leveraging these resources depends in part on mechanistic understanding for diffusive processes within walls. Common wood protection treatments biomass conversion to create biorefinery feedstocks feature ion or solvent diffusion the wall. X-ray fluorescence microscopy experiments have determined that ionic rates dependent wall hydration as well species through...