A5032506841- Enzyme Structure and Function
- Nuclear Physics and Applications
- Protein Structure and Dynamics
- Mass Spectrometry Techniques and Applications
- Enzyme Production and Characterization
- Biofuel production and bioconversion
- Advanced NMR Techniques and Applications
- Enzyme-mediated dye degradation
- Neonatal Health and Biochemistry
- Microbial bioremediation and biosurfactants
- Aldose Reductase and Taurine
- Biochemical and Molecular Research
- Porphyrin and Phthalocyanine Chemistry
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Enzyme Catalysis and Immobilization
- Photosynthetic Processes and Mechanisms
- Electron Spin Resonance Studies
- Metal-Catalyzed Oxygenation Mechanisms
- Spectroscopy and Quantum Chemical Studies
- Microbial Metabolic Engineering and Bioproduction
- Redox biology and oxidative stress
- Radiation Detection and Scintillator Technologies
- Pharmacogenetics and Drug Metabolism
- Porphyrin Metabolism and Disorders
North Carolina State University
2016-2025
Oak Ridge National Laboratory
2016-2025
North Central State College
2021
Carnegie Institution for Science
2018
Geophysical Laboratory
2018
Institut Laue-Langevin
2004-2009
Los Alamos National Laboratory
2008
Bethel University
2008
European Molecular Biology Laboratory
2004-2005
Max Delbrück Center
2004
Some of the improvements in SHELX2013 make SHELXL convenient to use for refinement macromolecular structures against neutron data without support X-ray data. The new NEUT instruction adjusts behaviour SFAC as well default bond lengths AFIX instructions. This work presents a protocol on how protein It includes restraints extending Engh & Huber [Acta Cryst. (1991), A47, 392-400] H atoms and discusses several features that program particularly useful investigation with diffraction. SHELXL2013...
Abstract Lytic polysaccharide monooxygenases have attracted vast attention owing to their abilities disrupt glycosidic bonds via oxidation instead of hydrolysis and enhance enzymatic digestion recalcitrant substrates including chitin cellulose. We determined high‐resolution X‐ray crystal structures an enzyme from Neurospora crassa in the resting state a copper(II) dioxo intermediate complex formed absence substrate. also revealed “pre‐bound” molecular oxygen adjacent active site. An...
The first high-resolution neutron protein structure of perdeuterated rubredoxin from Pyrococcus furiosus ( Pf Rd) determined using the new IMAGINE macromolecular crystallography instrument at Oak Ridge National Laboratory is reported. Neutron diffraction data extending to 1.65 Å resolution were collected a relatively small 0.7 mm 3 Rd crystal 2.5 d (60 h) beam time. refined contains 371 out 391, or 95%, D atoms and 58 solvent molecules. designed provide near atomic (1.5 Å) crystals with...
The scattering of neutrons can be used to provide information on the structure and dynamics biological systems multiple length time scales. Pursuant a National Science Foundation-funded workshop in February 2018, recent developments this field are reviewed here, as well future prospects that expected given advances sources, instrumentation computational power methods. Crystallography, solution scattering, dynamics, membranes, labeling imaging examined. For extraction maximum information,...
The nonstructural protein 3 (NSP3) macrodomain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (Mac1) removes adenosine diphosphate (ADP) ribosylation posttranslational modifications, playing a key role in the immune evasion capabilities virus responsible for disease 2019 pandemic. Here, we determined neutron and x-ray crystal structures SARS-CoV-2 NSP3 using multiple forms, temperatures, pHs, across apo ADP-ribose–bound states. We characterize extensive solvation Mac1 active...
Metalloproteins perform a diverse array of redox-related reactions facilitated by the increased chemical functionality afforded their metallocofactors. Lytic polysaccharide monooxygenases (LPMOs) are class copper-dependent enzymes that responsible for breakdown recalcitrant polysaccharides via oxidative cleavage at glycosidic bond. The activated copper-oxygen intermediates and mechanism formation remains to be established. Neutron protein crystallography which permits direct visualization...
We present results of combined studies the enzyme human aldose reductase (h-AR, 36 kDa) using single-crystal x-ray data (0.66 A, 100K; 0.80 15K; 1.75 293K), neutron Laue (2.2 and quantum mechanical modeling. These complementary techniques unveil internal organization mobility hydrogen bond network that defines properties catalytic engine, explaining how this promiscuous overcomes simultaneous requirements efficiency promiscuity offering a general mechanistic view for class enzymes.
Alginate lyases (ALs) catalyze the depolymerization of brown macroalgae alginates, widely used naturally occurring polysaccharides. Their molecular reaction mechanism remains elusive due to lack catalytically competent Michaelis-Menten-like complex structures. Here, we provide structural snapshots and dissect mannuronan-specific ALs from family 7 polysaccharide (PL7), employing time-resolved NMR, X-ray, neutron crystallography, QM/MM simulations. We reveal protonation state critical active...
Ezrin is a member of the ezrin-radixin-moesin family (ERM) adapter proteins that are localized at interface between cell membrane and cortical actin cytoskeleton, they regulate variety cellular functions. The structure representing dormant closed conformation an ERM protein has previously been determined by x-ray crystallography. Here, using contrast variation small angle neutron scattering, we reveal structural changes full-length ezrin upon binding to signaling lipid phosphatidylinositol...
RAS GTPase is a prototype for nucleotide-binding proteins that function by cycling between GTP and GDP, with hydrogen atoms playing an important role in the hydrolysis mechanism. It one of most well studied superfamily small GTPases, which has representatives wide range cellular functions. These share GTP-binding pocket highly conserved motifs promote to GDP. The neutron crystal structure presented here strongly supports protonated γ-phosphate at physiological pH. This counters notion...
Neutron diffraction data have been collected to 2.2 Å resolution from a small (0.15 mm3) crystal of perdeuterated human aldose reductase (h-AR; MW = 36 kDa) in order help determine the protonation state enzyme. h-AR belongs aldo–keto family and is implicated diabetic complications. Its ternary complexes (h-AR–coenzyme NADPH–selected inhibitor) provide good model study both enzymatic mechanism inhibition. Here, successful production fully deuterated [h-AR(D)], subsequent crystallization...
The IMAGINE and MaNDi instruments, located at Oak Ridge National Laboratory High Flux Isotope Reactor Spallation Neutron Source, respectively, are powerful tools for determining the positions of hydrogen atoms in biological macromolecules their ligands, orienting water molecules, differentiating chemical states macromolecular structures. possibility to model deuterium neutron structures arises from strong interaction neutrons with nuclei these isotopes. Positions can be unambiguously...
The recently discovered lytic polysaccharide monooxygenases (LPMOs) are Cu-containing enzymes capable of degrading substrates oxidatively. generally accepted first step in the LPMO reaction is reduction active-site metal ion from Cu 2+ to + . Here we have used a systematic diffraction data collection method monitor structural changes two AA9 LPMOs, one Lentinus similis ( Ls AA9_A) and Thermoascus aurantiacus Ta AA9_A), as photoreduced X-ray beam. For AA9_A, protein produced different...
The locations of H atoms in biological structures can be difficult to determine using X-ray diffraction methods. Neutron offers a relatively greater scattering magnitude from and D atoms. Here, 1.65 A resolution neutron studies fully perdeuterated selectively CH(3)-protonated crystals Pyrococcus furiosus rubredoxin (D-rubredoxin HD-rubredoxin, respectively) at room temperature (RT) are described, as well 1.1 the same protein both RT 100 K. two techniques quantitatively compared terms their...
Optimal enzyme activity depends on a number of factors, including structure and dynamics. The role is well recognized; however, the linkage between protein dynamics has given rise to contentious debate. We have developed an approach that uses aqueous mixture organic solvent control functionally relevant (without changing structure), which in turn modulates activity. Using this approach, we predicted hydride transfer reaction catalyzed by dihydrofolate reductase (DHFR) from Escherichia coli...
Perdeuterated and hydrogenated cytochrome P450cam (P450cam), from Pseudomonas putida, has been characterized concerning thermal stability structural dynamics. For the first time, Fourier transform infrared (FTIR) spectroscopy was used to characterize a perdeuterated protein. The secondary structure compositions were determined fitted amide I' spectral region, giving band populations at 10 °C for protein of 22% between 1605 1624 cm-1 (β-sheets), 47% 1633 1650 (α-helix (29%) plus...