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The Rotational Spectrum Of The Fed Radical In Its X4Δ State, Measured By Far-Infrared Laser Magnetic Resonance, Michael Jackson, Lyndon R. Zink, Jonathan P. Towle, Neil Riley, John M. Brown Apr 2009

The Rotational Spectrum Of The Fed Radical In Its X4Δ State, Measured By Far-Infrared Laser Magnetic Resonance, Michael Jackson, Lyndon R. Zink, Jonathan P. Towle, Neil Riley, John M. Brown

All Faculty Scholarship for the College of the Sciences

Transitions between the spin-rotational levels of the FeD radical in the v = 0level of the X 4Δ ground state have been detected by the technique of laser magnetic resonance at far-infrared wavelengths. Pure-rotational transitions have been observed for the three lowest spin components. Lambda-type doubling is resolved on all the observed transitions; nuclear hyperfine structure is not observed. The energy levels of FeD are strongly affected by the breakdown of the Born–Oppenheimer approximation and cannot be modeled accurately by an effective Hamiltonian. The data are therefore fitted to an empirical formula to yield term values and g-factors for …


Synthesis Of 2,4,5-Triaminocyclohexane Carboxylic Acid As A Novel 2-Deoxystreptamine Mimetic, Sarah Elizabeth Roberts Apr 2009

Synthesis Of 2,4,5-Triaminocyclohexane Carboxylic Acid As A Novel 2-Deoxystreptamine Mimetic, Sarah Elizabeth Roberts

Theses and Dissertations

RNAs have become increasingly recognized as possible drug targets due to their involvement in important biochemical functions, as well as their unique but well-defined structures. Recently published crystal structures depict the binding of a series of aminoglycosides- or more specifically- 2-deoxystretamine (2-DOS), the most preserved central scaffold of aminoglycosides, to a conserved 5'-GU-3'region on their target RNAs. A novel unnatural γ-amino acid, 1, has been synthesized using 2-deoxystreptamine as a template through structure-based rational design. The unnatural amino acid has been designed to replace a glycosidic linkage with an amide bond, which may limit the promiscuous binding characteristics of aminoglycosides …


Structure–Mutagenicity Relationships And Energies Of 1-, And 2-Nitrotriphenylenes [Abstract], Kefa Karimu Onchoke Apr 2009

Structure–Mutagenicity Relationships And Energies Of 1-, And 2-Nitrotriphenylenes [Abstract], Kefa Karimu Onchoke

Faculty Publications

No abstract provided.


Subunit-Selective Interrogation Of Co Recombination In Carbonmonoxy Hemoglobin By Isotope-Edited Time-Resolved Resonance Raman Spectroscopy, Gurusamy Balakrishnan, Xiaojie Zhao, Edyta Podstawska, Leonard M. Proniewicz, James R. Kincaid, Thomas G. Spiro Apr 2009

Subunit-Selective Interrogation Of Co Recombination In Carbonmonoxy Hemoglobin By Isotope-Edited Time-Resolved Resonance Raman Spectroscopy, Gurusamy Balakrishnan, Xiaojie Zhao, Edyta Podstawska, Leonard M. Proniewicz, James R. Kincaid, Thomas G. Spiro

Chemistry Faculty Research and Publications

Hemoglobin (Hb) is an allosteric tetrameric protein made up of αβ heterodimers. The α and β chains are similar, but are chemically and structurally distinct. To investigate dynamical differences between the chains, we have prepared tetramers in which the chains are isotopically distinguishable, via reconstitution with 15N-heme. Ligand recombination and heme structural evolution, following HbCO dissociation, was monitored with chain selectivity by resonance Raman (RR) spectroscopy. For α but not for β chains, the frequency of the ν4 porphyrin breathing mode increased on the microsecond time scale. This increase is a manifestation of proximal tension in the Hb …


Nano-Imprinted Thin Films Of Reactive, Azlactone-Containing Polymers: Combining Methods For The Topographic Patterning Of Cell Substrates With Opportunities For Facile Post-Fabrication Chemical Functionalization, Nathaniel J. Fredin, Adam H. Broderick, Maren E. Buck, David M. Lvnn Apr 2009

Nano-Imprinted Thin Films Of Reactive, Azlactone-Containing Polymers: Combining Methods For The Topographic Patterning Of Cell Substrates With Opportunities For Facile Post-Fabrication Chemical Functionalization, Nathaniel J. Fredin, Adam H. Broderick, Maren E. Buck, David M. Lvnn

Chemistry: Faculty Publications

Approaches to the fabrication of surfaces that combine methods for the topographic patterning of soft materials with opportunities for facile, post-fabrication chemical functionalization could contribute significantly to advances in biotechnology and a broad range of other areas. Here, we report methods that can be used to introduce well defined nano- and microscale topographic features to thin films of reactive polymers containing azlactone functionality using nanoimprint lithography (NIL). We demonstrate that NIL can be used to imprint topographic patterns into thin films of poly(2-vinyl-4,4- dimethylazlactone) and a copolymer of methyl methacrylate and 2-vinyl- 4,4-dimethylazlactone using silicon masters having patterns of grooves …


Controlled Assembly Of Rodlike Viruses With Polymers, Tao Li, Laying Wu, Nisaraporn Suthiwangcharoen, Michael A. Bruckman, Dayton Cash, Joan S. Hudson, Soumitra Ghoshroy, Qian Wang Apr 2009

Controlled Assembly Of Rodlike Viruses With Polymers, Tao Li, Laying Wu, Nisaraporn Suthiwangcharoen, Michael A. Bruckman, Dayton Cash, Joan S. Hudson, Soumitra Ghoshroy, Qian Wang

Faculty Publications

A practical method to assemble rodlike tobacco mosaic virus and bacteriophage M13 with polymers was developed, which afforded a 3D core–shell composite with morphological control.


Role Of Molecular Chaperones In G Protein B5-Regulator Of G Protein Signaling Dimer Assembly And G Protein By Dimer Specificity, Alyson Cerny Howlett Apr 2009

Role Of Molecular Chaperones In G Protein B5-Regulator Of G Protein Signaling Dimer Assembly And G Protein By Dimer Specificity, Alyson Cerny Howlett

Theses and Dissertations

In order for G protein signaling to occur, the G protein heterotrimer must be assembled from its nascent polypeptides. The most difficult step in this process is the formation of the Gβγ dimer from the free subunits since both are unstable in the absence of the other. Recent studies have shown that phosducin-like protein (PhLP1) works as a co-chaperone with the cytosolic chaperonin complex (CCT) to fold Gβ and mediate its interaction with Gγ. However, these studies did not address questions concerning the scope of PhLP1 and CCT-mediated Gβγ assembly, which are important questions given that there are four Gβs …


Pat Proteins, An Ancient Family Of Lipid Droplet Proteins That Regulate Cellular Lipid Stores. Biochim Biophys Acta, John Tansey Apr 2009

Pat Proteins, An Ancient Family Of Lipid Droplet Proteins That Regulate Cellular Lipid Stores. Biochim Biophys Acta, John Tansey

Chemistry Faculty Scholarship

The PAT family of lipid droplet proteins includes 5 members in mammals: perilipin, adipose differentiation-related protein (ADRP), tail-interacting protein of 47 kiloDaltons (TIP47), S3-12, and OXPAT. Members of this family are also present in evolutionarily distant organisms, including insects, slime molds and fungi. All PAT proteins share sequence similarity and the ability to bind intracellular lipid droplets, either constitutively or in response to metabolic stimuli, such as increased lipid flux into or out of lipid droplets. Positioned at the lipid droplet surface, PAT proteins manage access of other proteins (lipases) to the lipid esters within the lipid droplet core and …


Activation Energy Of The Formation Of The Allylic Carbocation In The Acid Catalyzed Dehydration Of 4-Methylcyclohexanol, Dequina Nicholas Apr 2009

Activation Energy Of The Formation Of The Allylic Carbocation In The Acid Catalyzed Dehydration Of 4-Methylcyclohexanol, Dequina Nicholas

Capstone Research Projects

The existence of a persisting allylic compound at equilibrium of the dehydration of 4-methyl cyclohexanol in 80% w/w sulfuric acid is supported by absorbance vs. time plots from UV-vis analysis . The peak seen at 305 nm is an indication of the formation of an allylic carbocation over time and therefore can support a proposed mechanism for this reaction. Kinetic analysis of the compound at 35.0°C, 48.5°C, 60.0°C, and 66.8°C shows that the dehydration reaction is first order with rate constants of 1.83 x 10-5s-1 , 1.27 x 10-4s-1 , 9.28x10-4s-1, and 9.55x10-4s-1 respectively for each temperature and an activation …


Chemistry & Biochemistry Newsletter, Department Of Chemistry & Biochemistry, South Dakota State University Apr 2009

Chemistry & Biochemistry Newsletter, Department Of Chemistry & Biochemistry, South Dakota State University

Chemistry & Biochemistry Newsletter: 2002-2015

Inside:

Page 2 Two majors win Schultz-Werth Awards

Page 3 Building Update

Page 4 Nagyvary is Lardy Lecture speaker; Raynie Gives Earth Day Talk; Logue Work Recognized; Grad student joins Young Chemists in Cancer Research committee

Page 5 Pravecek retires from Clinical Laboratory Teaching; Chem Grad student selected for national conference

Page 6 2008-2009 Chemistry and Biochemistry Graduates

Page 7 New Research Center Will Find New Uses for Light; Tanaka Undergraduate Award

Page 8 Scholarships and Award Winners


Potential Role Of Micro-Algae On Global Energy Supply, Sage Callaway-Keeley, Stephanie Huynh Apr 2009

Potential Role Of Micro-Algae On Global Energy Supply, Sage Callaway-Keeley, Stephanie Huynh

Student Research Posters

The most effective ways to reduce CO2 emissions are to improve the energy efficiency of each economic sector and to reduce the cutting of tropical and temperate forests around the world. These options, however, may not fully reach their technical and economic potential due to various political and socioeconomic. The most practical of these is to increase CO2 sinks through photosynthesis in both standing tree biomass and in ocean primary producers. The use of marine algae as CO2 sinks is for large-scale CO2 mitigation: the use of phytoplankton through Fe fertilization and macro algal (kelp) farms, which can be used …


A Theoretical Study Of Methanol Oxidation Mechanisms By Methanol Dehydrogenase Enzymes For Fuel Cell Applications, Nagesh B. Idupulapati Apr 2009

A Theoretical Study Of Methanol Oxidation Mechanisms By Methanol Dehydrogenase Enzymes For Fuel Cell Applications, Nagesh B. Idupulapati

Doctoral Dissertations

Enzymes are considered for electrochemical generation of power in fuel cells. Methanol dehydrogenase (MDH) is one such enzyme, which has been used as an anodic catalyst for a methanol-fed biofuel cell producing enough power for small electronic device applications. In practice, however, there are power output limitations associated with this MDH fuel cell, which may potentially be eliminated or reduced if the reactivity of this enzyme during the oxidation of methanol at the molecular level is clearly understood.

Two mechanisms for the methanol oxidation process by MDH have been proposed in the literature, Addition-Elimination (A-E) and Hydride Transfer (H-T), but …


Kinetic Studies On Enzyme-Catalyzed Reactions: Oxidation Of Glucose, Decomposition Of Hydrogen Peroxide And Their Combination, Zhimin Tao, Ryan A. Raffel, Abdul-Kader Souid, Jerry Goodisman Apr 2009

Kinetic Studies On Enzyme-Catalyzed Reactions: Oxidation Of Glucose, Decomposition Of Hydrogen Peroxide And Their Combination, Zhimin Tao, Ryan A. Raffel, Abdul-Kader Souid, Jerry Goodisman

Chemistry - All Scholarship

The kinetics of the glucose oxidase-catalyzed reaction of glucose with O2, which produces gluconic acid and hydrogen peroxide, and the catalase-assisted breakdown of hydrogen peroxide to generate oxygen, have been measured via the rate of O2 depletion or production. The O2 concentrations in air-saturated phosphate-buffered salt solutions were monitored by measuring the decay of phosphorescence from a Pd phosphor in solution; the decay rate was obtained by fitting the tail of the phosphorescence intensity profile to an exponential. For glucose oxidation in the presence of glucose oxidase, the rate constant determined for the rate-limiting step was k = (3.0 ± …


Optical Properties Of Multilayer-Polyelectrolyte Films With Incorporated Gold Nanomaterials (Solid Nanoparticles And Hollow Nanoshells), Robert Watson Day Apr 2009

Optical Properties Of Multilayer-Polyelectrolyte Films With Incorporated Gold Nanomaterials (Solid Nanoparticles And Hollow Nanoshells), Robert Watson Day

Honors Theses

The growth of various multilayer‐polymer multilayer‐nanoparticle films was successfully achieved. Multilayer‐polymer multilayer‐nanoparticle films with 1, 3, and 5 polymer layers between nanoparticle layers exhibit significantly different optical properties due to the differences in magnitude of particle plasmon coupling. These film systems were also successfully extended to hollow gold nanoshells, which have significantly enhanced optical properties in comparison to solid gold nanoparticles of similar sizes. A proposal for utilizing this increased sensitivity of the gold nanoshells to explore the ‘microenvironments’ for optimizing potential sensing applications is also presented.


Frequency And Isostericity Of Rna Base Pairs, Craig L. Zirbel, Jesse Stombaugh, Eric Westhof Apr 2009

Frequency And Isostericity Of Rna Base Pairs, Craig L. Zirbel, Jesse Stombaugh, Eric Westhof

Chemistry Faculty Publications

Most of the hairpin, internal and junction loops that appear single-stranded in standard RNA secondary structures form recurrent 3D motifs, where non-WatsonCrick base pairs play a central role. Non-WatsonCrick base pairs also play crucial roles in tertiary contacts in structured RNA molecules. We previously classified RNA base pairs geometrically so as to group together those base pairs that are structurally similar (isosteric) and therefore able to substitute for each other by mutation without disrupting the 3D structure. Here, we introduce a quantitative measure of base pair isostericity, the IsoDiscrepancy Index (IDI), to more accurately determine which base pair substitutions can …


N- And C-Terminal Domains In Human Holocarboxylase Synthetase Participate In Substrate Recognition, Yousef I. Hassan, Hideaki Moriyama, Lars J. Olsen, Xin Bi, Janos Zempleni Apr 2009

N- And C-Terminal Domains In Human Holocarboxylase Synthetase Participate In Substrate Recognition, Yousef I. Hassan, Hideaki Moriyama, Lars J. Olsen, Xin Bi, Janos Zempleni

Hideaki Moriyama Publications

Holocarboxylase synthetase (HCS) catalyzes the binding of the vitamin biotin to carboxylases and histones. Carboxylases mediate essential steps in macronutrient metabolism. For example, propionyl- CoA carboxylase (PCC) catalyzes the carboxylation of propionyl-CoA in the metabolism of oddchain fatty acids. HCS comprises four putative domains, i.e., the N-terminus, the biotin transfer/ATP binding domain, a putative linker domain, and the C-terminus. Both N- and C-termini are essential for biotinylation of carboxylases by HCS, but the exact functions of these two domains in enzyme catalysis are unknown. Here we tested the hypothesis that N- and C-termini play roles in substrate recognition by HCS. …


Inside Unlv, Shane Bevell, Diane Russell, Michelle Mouton, Gian Galassi Apr 2009

Inside Unlv, Shane Bevell, Diane Russell, Michelle Mouton, Gian Galassi

Inside UNLV

No abstract provided.


Volume 02, Joseph A. Mann, Kathryn J. Greenly, Scott E. Jenkins, Andrew E. Puckette, Daniel M. Honey, Jeffery P. Ravenhorst, Jamie Elizabeth Mesrobian, Thomas Scott, Jay Crowell, Sarah Spangenberg, Amy S. Eason, Kenny Wolfe, Liz Hale, Rachel Bouchard, Will Semonco, Carley York, Ryan Higgenbothom, Adrienne Heinbaugh, Melissa Dorton, Madeline Hunter, June Ashmore, Clark Barkley, Jay Haley Apr 2009

Volume 02, Joseph A. Mann, Kathryn J. Greenly, Scott E. Jenkins, Andrew E. Puckette, Daniel M. Honey, Jeffery P. Ravenhorst, Jamie Elizabeth Mesrobian, Thomas Scott, Jay Crowell, Sarah Spangenberg, Amy S. Eason, Kenny Wolfe, Liz Hale, Rachel Bouchard, Will Semonco, Carley York, Ryan Higgenbothom, Adrienne Heinbaugh, Melissa Dorton, Madeline Hunter, June Ashmore, Clark Barkley, Jay Haley

Incite: The Journal of Undergraduate Scholarship

Introduction from Dean Dr. Charles Ross

Mike's Nite: New Jazz for an Old Instrument by Joseph A. Mann

Investigation of the use of Cucumis Sativus for Remediation Of Chromium from Contaminated Environmental Matrices: An Interdisciplinary Instrumental Analysis Project by Kathryn J. Greenly, Scott E. Jenkins, and Andrew E. Puckette

Development of GC-MS and Chemometric Methods for the Analysis of Accelerants in Arson Cases by Scott Jenkins

Building and Measuring Scalable Computing Systems by Daniel M. Honey and Jeffery P. Ravenhorst

Nomini Hall: A Case Study in the Use of Archival Resources as Guides for Excavation at An Archaeological Site by …


Microwave-Assisted Ruthenium Trichloride-Catalyzed Synthesis Of Pyrrole Fused With Indole System In Water, Debasish Bandyopadhyay, Antara Banik, Sahil Bhatta, Bimal K. Banik Apr 2009

Microwave-Assisted Ruthenium Trichloride-Catalyzed Synthesis Of Pyrrole Fused With Indole System In Water, Debasish Bandyopadhyay, Antara Banik, Sahil Bhatta, Bimal K. Banik

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

A simple and efficient microwave-induced ruthenium trichloride-catalyzed synthesis of pyrrole fused with indole system in water is developed by reacting commercially available isatin and 4-hydroxyproline.


Variation Of Benzyl Anions In Mgal-Layered Double Hydroxides: Fire And Thermal Properties In Pmma, Calistor Nyambo, Dan Chen, Shengpei Shu, Charles A. Wilkie Apr 2009

Variation Of Benzyl Anions In Mgal-Layered Double Hydroxides: Fire And Thermal Properties In Pmma, Calistor Nyambo, Dan Chen, Shengpei Shu, Charles A. Wilkie

Chemistry Faculty Research and Publications

Magnesium aluminum layered double hydroxides (MgAl-LDHs) intercalated with a range of benzyl anions were prepared using the coprecipitation method. The benzyl anions differ in functionality (i.e. carboxylate, sulfonate, and phosphonate) and presence or absence of an amino substituent. Various methods for preparing LDHs (i.e. ion exchange, coprecipitation and rehydration of the calcined LDH methods) have been compared with the MgAl-benzene phosphonate and their effect on fire and thermal properties was studied. After characterization, the MgAl-LDHs were melt-blended with poly(methyl methacrylate) (PMMA) at loadings of 3 and 10% by weight to prepare composites. Characterization of the LDHs and the PMMA composites …


Spectroscopic Studies Of Fluoranthene And 3-Nitrofluoranthene, Matthew Parks Mar 2009

Spectroscopic Studies Of Fluoranthene And 3-Nitrofluoranthene, Matthew Parks

Undergraduate Research Conference

Polycyclic aromatic hydrocarbons (PAHs) are known byproducts of anthropogenic sources including incomplete combustion of fossil fuels. They are known to be teratogenic, mutagenic and carcinogenic. This study investigated the spectral properties of fluoranthene and 3- nitrofluoranthene using NMR, UV-Vis and infrared techniques. The acquisition of spectral data provides a means to identify these compounds in mixtures and can be used which to develop model formulae for quantitation. A 2-D NMR method (HMQC ) was used for assigning 13C peaks. The infrared spectrum for 3-nitrofluoranthene showed characteristic strong absorption peaks at 1323 and 1516 cm-1 assigned to symmetric/asymmetric nitro stretches, respectively. …


Light-Regulated Sampling Of Protein Kinase Activity (Ii), Collaborative Project Mar 2009

Light-Regulated Sampling Of Protein Kinase Activity (Ii), Collaborative Project

Dyson College- Seidenberg School of CSIS : Collaborative Projects and Presentations

This entry adheres to the use of the quad chart template to provide a succinct description only of the current research project undertaken by the participants. It provides for the following information

1. Participants and Affiliations
2. Overall Project Goals
3. Illustrative picture
4. Specific research/artistic/pedagogic foci


Mammaglobin As A Potential Molecular Target For Breast Cancer Drug Delivery, Lian Zuo, Ly Li, Qian Wang, Timothy P. Fleming, Shaojin You Mar 2009

Mammaglobin As A Potential Molecular Target For Breast Cancer Drug Delivery, Lian Zuo, Ly Li, Qian Wang, Timothy P. Fleming, Shaojin You

Faculty Publications

Background Mammaglobin (MAM) has been used as a specific molecular marker for breast cancer diagnosis. Recently, several groups of researchers proposed a number of therapeutic strategies targeting this molecule. Some of the strategies are based upon an essential but not demonstrated hypothesis - mammaglobin is associated with the surface of breast cancer cells, which strongly disputes the therapeutic strategies. Results We conducted a computer-based predictive analysis and identified a small fragment at the N-end of MAM as a potential transmembrane domain. We provided several evidences to demonstrate the presence of the membrane-associated MAM. We isolated the membrane protein components from …


Functionalization, Characterization, And Applications Of Diamond Particles, Modification Of Planar Silicon, And Chemoetrics Analysis Of Ms Data, Li Yang Mar 2009

Functionalization, Characterization, And Applications Of Diamond Particles, Modification Of Planar Silicon, And Chemoetrics Analysis Of Ms Data, Li Yang

Theses and Dissertations

In spite of the stablility (lack of reactivity) of diamond powder, I have developed a method for tethering alkyl chains and polymers to deuterium/hydrogen-terminated diamond. One method is through ether linkages via thermolysis of di-tert-amyl peroxide (DTAP). This reaction with DTAP has also been applied to grow polymers on the diamond surface. The other method is atom transfer radical polymerization (ATRP), which was applied to grow polystyrene at the surface of diamond. Both polystyrene-modified diamond and sulfonated polystyrene-modified diamond can be prepared by either method, and can be used for solid phase extraction. Diamond stationary phases are stable under basic …


The First Attachment And Post-Functionalization Of Polybutadiene And Thio-Click Functionalized Polybutadiene On H-Terminated Si(111), Todd Devere Wickard Mar 2009

The First Attachment And Post-Functionalization Of Polybutadiene And Thio-Click Functionalized Polybutadiene On H-Terminated Si(111), Todd Devere Wickard

Theses and Dissertations

I report the attachment of polymers with pendant vinyl groups to hydrogen-terminated silicon(111) (Si(111)-H) under mild conditions. 1,2-addition polybutadiene (Mw 3200-3500) was attached to Si(111)-H at room temperature with visible light. I also report the partial functionalization, in solution, of 1,2-addition polybutadiene with various thiols using thiol-click chemistry. These compounds bind to Si(111)-H via visible light activation. The partially functionalized polybutadienes allow further functionalization at the surface through unreacted carbon-carbon double bonds. Surfaces were characterized with contact angle goniometry, spectroscopic ellipsometry, X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), and atomic force microscopy (AFM).


Tobacco Mosaic Virus Templated Synthesis Of One Dimensional Inorganic–Polymer Hybrid Fibres, Jianhua Rong, Fiona Oberbeck, Xinnan Wang, Xiaodong Li, Jerry Oxsher, Zhongwei Niu, Qian Wang Mar 2009

Tobacco Mosaic Virus Templated Synthesis Of One Dimensional Inorganic–Polymer Hybrid Fibres, Jianhua Rong, Fiona Oberbeck, Xinnan Wang, Xiaodong Li, Jerry Oxsher, Zhongwei Niu, Qian Wang

Faculty Publications

Inorganic–polymer hybrid nanofibres were prepared by using a rod-like tobacco mosaic virus (TMV) as a template. With tetraethylorthosilicate (TEOS) as a precursor, long silica-coated TMVfibres were formed via a head-to-tail assembly, which showed a substantial increase of the elastic modulus. Furthermore, homogenous titania–TMV hybrid fibres could be prepared using polyaniline-coated TMV fibres as a template, which were used to form a composite film that was able to sense liquefied petroleum gases.


Inactivation Of [Fe-Fe]-Hydrogenase By O2. Thermodynamics And Frontier Molecular Orbitals Analyses, Daniela Dogaru, Stefan Motiu, Valentin Gogonea Mar 2009

Inactivation Of [Fe-Fe]-Hydrogenase By O2. Thermodynamics And Frontier Molecular Orbitals Analyses, Daniela Dogaru, Stefan Motiu, Valentin Gogonea

Chemistry Faculty Publications

The oxidation of H-cluster in gas phase, and in aqueous enzyme phase, has been investigated by means of quantum mechanics (QM) and combined quantum mechanics–molecular mechanics (QM/MM). Several potential reaction pathways (in the above-mentioned chemical environments) have been studied, wherein only the aqueous enzyme phase has been found to lead to an inhibited hydroxylated cluster. Specifically, the inhibitory process occurs at the distal iron (Fed) of the catalytic H-cluster (which isalso the atom involved in H2 synthesis). The processes involved in the H-cluster oxidative pathways are O2 binding, e− transfer, protonation, and H2O removal. We found that oxygen binding is …


Catena-Poly[[(Pyridine-Κn)Copper(Ii)]-Μ3-Pyridine-2,6-Dicarboxylato-Κ3o2:O2′,N,O6:O6′], Manoj Trivedi, Daya Pandey, Nigam Rath Mar 2009

Catena-Poly[[(Pyridine-Κn)Copper(Ii)]-Μ3-Pyridine-2,6-Dicarboxylato-Κ3o2:O2′,N,O6:O6′], Manoj Trivedi, Daya Pandey, Nigam Rath

Chemistry & Biochemistry Faculty Works

In the title compound, [Cu(C7H3NO4)(C5H5N)]n, the CuII atom is in a slightly distorted octa­hedral coordination environment. Each CuII atom is bound to two N atoms and one O atom of the pyridine­dicarboxyl­ate (PDA) ligand in a tridentate manner, one N atom of the pyridine mol­ecule and two bridging carboxyl­ate O atoms of adjacent PDA ligands, leading to a linear one-dimensional chain running along the c axis. These chains are further assembled via weak C-H...O and [pi]-[pi] inter­actions into a three-dimensional supra­molecular network structure. The centroid-centroid distance between the [pi]-[pi] inter­acting pyridine rings is 3.9104 (13) Å. The two N atoms …


Polyelectrolyte-Linked Film Assemblies Of Nanoparticles And Nanoshells: Growth, Stability, And Optical Properties, Anne A. Galyean, Justin Malinowski, Robert W. Day, Kevin W. Kittredge, Michael C. Leopold Mar 2009

Polyelectrolyte-Linked Film Assemblies Of Nanoparticles And Nanoshells: Growth, Stability, And Optical Properties, Anne A. Galyean, Justin Malinowski, Robert W. Day, Kevin W. Kittredge, Michael C. Leopold

Chemistry Faculty Publications

Multi-layer films of nanoparticles and nanoshells featuring various polymeric linkage molecules have been assembled and their optical properties characterized. The growth dynamics, including molecular weight effects, and stability of the various nanoparticle film constructions, using both single polymer as well as combinations of alternating charge polyelectrolytes as linking mechanisms, are presented. The polymeric linkers studied include poly-L-lysine, poly-L-arginine, poly(allylamine hydrochloride), and polyamidoamine dendrimers. Significantly air stable films were achieved with the use of multi-layered polymeric bridges between the nanoparticles and nanoshells. Optical sensitivity normally observed with these nanomaterials in solution was observed for their corresponding film geometries, with the nanoshell …


Role Of The Oxyferrous Heme Intermediate And Distal Side Adduct Radical In The Catalase Activity Of Mycobacterium Tuberculosis Katg Revealed By The W107f Mutant, Xiangbo Zhao, Shengwei Yu, Kalina Ranguelova, Javier Suarez, Leonid Metlitsky, Johannes Schelvis, Richard S. Magliozzo Mar 2009

Role Of The Oxyferrous Heme Intermediate And Distal Side Adduct Radical In The Catalase Activity Of Mycobacterium Tuberculosis Katg Revealed By The W107f Mutant, Xiangbo Zhao, Shengwei Yu, Kalina Ranguelova, Javier Suarez, Leonid Metlitsky, Johannes Schelvis, Richard S. Magliozzo

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

Catalase-peroxidase (KatG) is essential in Mycobacterium tuberculosis for oxidative stress management and activation of the antitubercular pro-drug isoniazid. The role of a unique distal side adduct found in KatG enzymes, involving linked side chains of residues Met255, Tyr229, and Trp107 (MYW), in the unusual catalase activity of KatG is addressed here and in our companion paper (Suarez, J., Ranguelova, K., Jarzecki, A. A., Manzerova, J., Krymov, V., Zhao, X., Yu, S., Metlitsky, L., Gerfen, G. J., and Magliozzo, R. S. (2009) J. Biol. Chem. 284, in press). The KatG[W107F] mutant exhibited severely reduced catalase activity yet normal peroxidase activity, and …