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CreatorTitleDescriptionSubjectDate
1 Poulter, Charles Dale(S)-Geranylgeranylglyceryl phosphate synthase. Purification and characterization of the first pathway-specific enzyme in archaebacterial membrane lipid biosynthesisThe first pathway-specific step in the biosynthesis of the core membrane diether lipids in archaebacteria is the alkylation of the primary hydroxyl group in (S)-glyceryl phosphate by geranylgeranyl diphosphate. The reaction is catalyzed by (S)-3-O-geranylgeranylglyceryl phosphate ((S)-GGGP) synthase...Polyacrylamide gel; Molecular weight1993-10-15
2 Poulter, Charles Dale; Davis, Darrell R.15N labeled e. coli tRNAMet, tRNAGlu, tRNATyr, and tRNAPhe. Double resonance and two dimensional NMR of H-N1 units in pseudouridineThe N1 imino units in Escherichia coli tRNAfMet, tRNAGlu, tRNAPhe, and tRNATyr were studied by 1H-15N NMR using three different techniques to suppress signals of protons not attached to 15N. Two of the procedures, Fourier internuclear difference spectroscopy and two-dimensional forbidden echo spectr...Escherichia coli; Magnetic resonance spectroscopy; Nucleic acid conformation1985-08-15
3 Poulter, Charles Dale; Davis, Darrell R.15N-labeled Escherichia coli tRNAfMet, tRNAGlu, tRNATyr, and tRNAPhe. Double resonance and two-dimensional NMR of N1-labeled pseudouridine.The N1 imino units in Escherichia coli tRNAfMet, tRNAGlu, tRNAPhe, and tRNATyr were studied by 1H-15N NMR using three different techniques to suppress signals of protons not attached to 15N. Two of the procedures, Fourier internuclear difference spectroscopy and two-dimensional forbidden echo spectr...Escherichia coli; Magnetic resonance spectroscopy; Nitrogen; Nucleic acid conformation1985-08-15
4 Poulter, Charles Dale; Davis, Darrell R.15N-labeled tRNA. Identification of 4-thiouridine in Escherichia coli tRNASer1 and tRNATyr2 by 1H-15N two-dimensional NMR spectroscopy.Uridine is uniquely conserved at position 8 in elongator tRNAs and binds to A14 to form a reversed Hoogsteen base pair which folds the dihydrouridine loop back into the core of the L-shaped molecule. On the basis of 1H NMR studies, Hurd and co-workers (Hurd, R. E., Robillard, G. T., and Reid, B. R. ...Magnetic resonance spectroscopy1986-09-15
5 Poulter, Charles Dale; Davis, Darrell R.15N-labeled tRNA. Identification of dihydrouridine in Escherichia coli tRNAfMet, tRNALys, and tRNAPhe by 1H-15N two-dimensional NMR.The N3 imino units of dihydrouridine were identified in samples of 15N-labeled Escherichia coli tRNAfMet, tRNALys, and tRNAPhe by 1H-15N two-dimensional NMR. The peaks for dihydrouridine had high field 1H (9.7-9.8 ppm) and 15N (147.8-149.5 ppm) chemical shifts. Assignments were made by 1H-15N chemic...Hydrogen Bonding; Magnetic Resonance Spectroscopy; Magnetic Resonance Spectroscopy1986-03-15
6 Miller, Joel Steven1H NMR investigation of the magnetic spin configuration in the molecule-based ferrimagnet [MnTFPP][TCNE]1H NMR line-shape measurements have been performed in the linear chain molecule-based ferrimagnet [MnTFPP][TCNE].xPhMe (TFPP=tetrakis(4-fluorophenyl)porphinato; TCNE=tetracyanoethylene) as a function of temperature. Hyperfine shifts of opposite sign were observed indicating the presence of two oppo...Magnetization; Magnets; Paramagnetic2002
7 Morse, Michael David???X??+ band systems of jet-cooled ScCo and YCoRotationally resolved resonant two-photon ionization (R2PI) spectra of ScCo and YCo are reported. The measured spectra reveal that these molecules possess ground electronic states of 1?+ symmetry, as previously found in the isoelectronic Cr2 and CrMo molecules. The ground state rotational constant...2010
8 Morse, Michael DavidA pair potentials study of matrix-isolated atomic zinc. II. Intersystem crossing in rare-gas clusters and matricesThe mechanism of 4p 1P1?4p 3PJ intersystem crossing (ISC) following excitation of the 4p 1P1 level of matrix-isolated atomic zinc is investigated using a pair potentials approach. This is achieved by extending earlier ISC calculations on the Zn?RG2 and Zn?RG3 complexes to the square planar Zn?RG4 ...1998
9 Voth, Gregory AlanAb initio calculations of reactive pathways for ?-octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (?-HMX)Using the BLYP and B3LYP level of density functional theory, four possible decomposition reaction pathways of HMX in the gas phase were investigated: N?NO2 bond dissociation, HONO elimination, C?N bond scission of the ring, and the concerted ring fission. The energetics of each of these four mechan...Ab initio calculations; Reactive pathways; HMX2000
10 Armentrout, Peter B.Activation of methane by gold cations: guided ion beam and theoretical studiesThe potential energy surface for activation of methane by the third-row transition metal cation, Au+, is studied experimentally by examining the kinetic energy dependence of this reaction using guided ion beam tandem mass spectrometry. A flow tube ion source produces Au+ primarily in its 1S0 (5d10) ...2006
11 Armentrout, Peter B.Activation of methane by size-elected iron cluster cations, Fen+ (n=2-15): cluster-CHx (x=0-3) bond energies and reaction mechanismsThe kinetic energy dependences of the reactions of Fen + (n=2 - 15) with CD4 are studied in a guided ion beam tandem mass spectrometer over the energy range of 0-10 eV. All reactions exhibit thresholds and two main products, FenD+ and FenCD2+, are formed.Metal clusters; Iron ions; Bond energies; Dehydrogenation; Endothermic reactions; Transition metal ions2001
12 Armentrout, Peter B.Alkali metal cation interactions with 12-crown-4 in the gas phase: revisitedQuantitative interactions of alkali metal cations with the cyclic 12-crown-4 polyether ligand (12C4) are studied. Experimentally, Rb+(12C4) and Cs+(12C4) complexes are formed using electrospray ionization and their bond dissociation energies (BDEs) determined using threshold collision-induced dissoc...2012-01-01
13 Miller, Joel Steven; Epstein, Arthur J.Anomalous charge transport phenomena in the molecular-based magnet V(TCNE)x.y(solvent)We present charge transport studies on recently developed molecular-based magnets V(TCNE)x. y(solvent) (TCNE= tetracyanoethylene) which show local magnetic ordering at temperatures, T, as high as 400 K. V(TCNE), .y(solvent) prepared from the solvent CH2Cl2 has o(300 K) - 10-3 S/cm, and that prepar...Frequency; Conductivity; Spin1993
14 Miller, Joel Steven; Epstein, Arthur J.Anomalous magnetoresistance in high-temperature organic-based magnetic seminconducting V(TCNE)x filmsAnomalous positive magnetoresistance (MR) in high temperature organic-based magnet V(TCNE)x (TCNE=tetracynoethylene) thin films is reported. MR increases linearly with applied magnetic field and shows a maximum at the ferrimagnetic ordering temperature. The suggested roles of oppositely spin pola...Spin; Ferrimagnetic; Resistance2003
15 Miller, Joel Steven; Epstein, Arthur J.Anomalous relaxation in a quasi-one-dimensional fractal cluster glassThe low-temperature spin glass state of the quasi-1D organic-based magnet [MnTPP]+[TCNE]- .x(1,3-C6H4Cl2) has unusually long relaxation times due to frustration induced by dipole-dipole interactions between fractal spin clusters. This long relaxation is investigated with in-field relaxation measurem...Sweep rate; Bifurcation; Magnetization2004
16 Poulter, Charles Dale; Jiang, YunfengBTS1 encodes a geranylgeranyl diphosphate synthase in Saccharomyces cerevisiaeProtein prenylation utilizes different types of isoprenoids groups, namely farnesyl and geranylgeranyl, to modify proteins. These lipophilic moieties attach to carboxyl-terminal cysteine residues to promote the association of soluble proteins to membranes. Most prenylated proteins are geranylgeranyl...Amino Acid Sequence; Cloning, Molecular; Gene Expression1995-09-15
17 Minteer, Shelley D.Bio-solar cells incorporating catalase for stabilization of thylakoid bioelectrodes during direct photoelectrocatalysisThylakoid membranes have been proposed for electrochemical solar energy conversion, but they have been plagued with short term instability. In this paper, thylakoid membranes extracted from Spinacia oleracea were physically adsorbed onto Toray paper electrodes with and without catalase, followed by ...2012-01-01
18 Truong, ThanhBranching ratio and pressure dependent rate constants of multichannel unimolecular decomposition of gas-phase ?-HMX: an ab initio dynamics studyThe dynamics of the initial thermal decomposition step of gas-phase ?-HMX is investigated using the master equation method. Both the NO2 fission and HONO elimination channels were considered. The structures, energies, and Hessian information along the minimum energy paths (MEP) of these two channels...Thermal decomposition; HMX2001
19 Armentrout, Peter B.C+(2P) + H2(D2,HD)→CH+(CD+) + H(D). I. Reaction cross sections and kinetic isotope effects from threshold to 15 eV c.m.Total cross sections for the reactions of carbon (1 + ) ions with isotopic molecular hydrogen (H2, D2 , and HD) to form methyliumylidene (CH+ and C D + ) have been measured using guided ion beam techniques. Cross sections are reported as a function of the translational energy of the reactants fro...Ion-molecule reactions; Isotope effects; Translational energy; Threshold behavior; Endothermic reactions1986
20 Armentrout, Peter B.C+(2P)+H2(D2,HD)→CH+(CD+)+H(D). I. Reaction cross sections and kinetic isotope effects from threshold to 15eV c.m.Total cross sections for the reactions of carbon (1 + ) ions with isotopic molecular hydrogen (H2, D2, and HD) to form methyliumylidene (CH+ and CD+) have been measured using guided ion beam techniques. Cross sections are reported as a function of the translational energy of the reactants from th...Methyliumylidene; Endothermic reactions; Isotope effect; Threshold energy1986
21 Borodai, Anastasia S.C-F bond activationActivation of Carbon-Fluorine Bonds in 2', 3', 4', 5', 6'-Pentafluoroacetophenone through a Transition Metal Complex- Manganese PentacarbonylCarbon; Fluorine; Bond; Activation2014-05-30
22 Poulter, Charles DaleCaaX proteases, Afc1p and Rce1p, have overlapping but distinct substrate specificitiesMany proteins that contain a carboxyl-terminal CaaX sequence motif, including Ras and yeast a-factor, undergo a series of sequential posttranslational processing steps. Following the initial prenylation of the cysteine, the three C-terminal amino acids are proteolytically removed, and the newly fo...Proteins; Enzymes; Hydrophobic2000
23 Orendt, Anita; Pugmire, Ronald J.Carbon-13 chemical shift tensors in polycyclic aromiatic compounds. 9. BiphenyleneThe principal values of the 13C chemical-shift tensors of natural abundance biphenylene were measured at room temperature with the FIREMAT experiment. Of 18 crystallographically distinct positions (three sets of six congruent carbons each), the three primary bands have been resolved into seven singl...Carbon-13; Chemical-shift tensors; Biphenylene; Polycyclic aromiatic compounds; FIREMAT2000
24 Poulter, Charles DaleCatalytic mechanism of Escherichia coli isopentenyl diphosphate isomerase involves Cys-67, Glu-116, and Tyr-104 as suggested by crystal structures of complexes with transition state analogues and irreversible inhibitorsIsopentenyl diphosphate (IPP):dimethylallyl diphosphate (DMAPP) isomerase is a key enzyme in the biosynthesis of isoprenoids. The reaction involves protonation and deprotonation of the isoprenoid unit and proceeds through a carbocationic transition state. Analysis of the crystal structures (2 A) of ...Catalytic Domain; Crystallography; Organophosphorus Compounds2003-04-04
25 Miller, Joel StevenCharacterization of novel TCNQ and TCNE 1 : 1 and 1 : 2 salts of the tetrakis(dimethyamino) ethylene dication, [{(CH3)2N}2C-C{N(CH3)2}2]2+Addition of TCNQ to a solution of tetrakis(dimethylamino)ethylene in MeCN produces the salt [TDAE][TCNQ]2; the dipositive cation, [{(CH3)2N}2C-C{N(CH3)2}2]2+, is nonplanar, with a dihedral angle of 63.9(o), while the TCNQ anions crystallize as [TCNQ]2 2- dimers with an interplanar separation of 3.1...Electron; Oxidations; Transfer1996
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