Open Access. Powered by Scholars. Published by Universities.®
Biochemistry, Biophysics, and Structural Biology Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Biochemistry (164)
- Chemistry (84)
- Physical Sciences and Mathematics (84)
- Analytical Chemistry (9)
- Medicine and Health Sciences (8)
-
- Microbiology (7)
- Molecular Biology (6)
- Environmental Chemistry (5)
- Organic Chemistry (5)
- Physical Chemistry (5)
- Chemicals and Drugs (4)
- Engineering (4)
- Environmental Sciences (4)
- Medicinal-Pharmaceutical Chemistry (4)
- Amino Acids, Peptides, and Proteins (3)
- Biology (3)
- Cell and Developmental Biology (3)
- Civil and Environmental Engineering (3)
- Environmental Engineering (3)
- Laboratory and Basic Science Research (3)
- Atmospheric Sciences (2)
- Ecology and Evolutionary Biology (2)
- Forest Sciences (2)
- Medical Sciences (2)
- Oceanography and Atmospheric Sciences and Meteorology (2)
- Pharmacology, Toxicology and Environmental Health (2)
- Pharmacy and Pharmaceutical Sciences (2)
- Wood Science and Pulp, Paper Technology (2)
- Institution
- Keyword
-
- Antifungal activity (8)
- Biochemistry (4)
- Flavin (4)
- Oxidation-Reduction (4)
- Animals (3)
-
- Binding Sites (3)
- Brain chemistry (3)
- Chemistry (3)
- Mutation (3)
- Proteins (3)
- 13C NMR (2)
- 5-iodo-8-quinolinol (2)
- Acetylation (2)
- Aerosol (2)
- Amino acid transport. Thermotoga maritima (2)
- Archaea (2)
- Bacteria (2)
- Bacterial binding protein (2)
- Biomass burning (2)
- Brain (2)
- Cell Nucleus (2)
- Cell and Molecular biology (2)
- DNA replication (2)
- Dichloro-8-quinolinols (2)
- Electron bifurcation (2)
- Electron transfer (2)
- Flavoenzyme (2)
- Flavoprotein (2)
- Fluorescence (2)
- Fluoroacetate (2)
Articles 31 - 60 of 175
Full-Text Articles in Biochemistry, Biophysics, and Structural Biology
Hmba Is A Putative Hsp70 Activator Stimulating Hexim1 Expression That Is Down-Regulated By Estrogen, Rati Lama, Chunfang Gan, Nethrie Idippily, Viharika Bobba, David Danielpour, Monica Montano, Bin Su Ph.D.
Hmba Is A Putative Hsp70 Activator Stimulating Hexim1 Expression That Is Down-Regulated By Estrogen, Rati Lama, Chunfang Gan, Nethrie Idippily, Viharika Bobba, David Danielpour, Monica Montano, Bin Su Ph.D.
Chemistry Faculty Publications
Hexamethylene bis-acetamide inducible protein 1 (HEXIM1) is identified as a novel inhibitor of estrogen stimulated breast cell growth, and it suppresses estrogen receptor-a transcriptional activity. HEXIM1 protein level has been found to be downregulated by estrogens. Recently, HEXIM1 has been found to inhibit androgen receptor transcriptional activity as well. Researchers have used Hexamethylene bisacetamide (HMBA) for decades to stimulate HEXIM1 expression, which also inhibit estrogen stimulated breast cancer cell gene activation and androgen stimulated prostate cancer gene activation. However, the direct molecular targets of HMBA that modulate the induction of HEXIM1 expression in mammalian cells have not been identified. Based …
Comparative Proteomic Analyses Of The Parietal Lobe From Rhesus Monkeys Fed A High-Fat/Sugar Diet With And Without Resveratrol Supplementation, Relative To A Healthy Diet: Insights Into The Roles Of Unhealthy Diets And Resveratrol On Function, Aaron M. Swomley, Judy C. Triplett, Jeriel T. Keeney, Govind Warrier, Kevin J. Pearson, Julie A. Mattison, Rafael De Cabo, Jian Cai, Jon B. Klein, D. Allan Butterfield
Comparative Proteomic Analyses Of The Parietal Lobe From Rhesus Monkeys Fed A High-Fat/Sugar Diet With And Without Resveratrol Supplementation, Relative To A Healthy Diet: Insights Into The Roles Of Unhealthy Diets And Resveratrol On Function, Aaron M. Swomley, Judy C. Triplett, Jeriel T. Keeney, Govind Warrier, Kevin J. Pearson, Julie A. Mattison, Rafael De Cabo, Jian Cai, Jon B. Klein, D. Allan Butterfield
Chemistry Faculty Publications
A diet consisting of a high intake of saturated fat and refined sugars is characteristic of a Western-diet and has been shown to have a substantial negative effect on human health. Expression proteomics were used to investigate changes to the parietal lobe proteome of rhesus monkeys consuming either a high fat and sugar (HFS) diet, a HFS diet supplemented with resveratrol (HFS+RSV), or a healthy control diet for 2 years. Here we discuss the modifications in the levels of 12 specific proteins involved in various cellular systems including metabolism, neurotransmission, structural integrity, and general cellular signaling following a nutritional intervention. …
Chemical Profiling And Chemical Standardization Of Vitex Negundo Using 13c Nmr, Fabian M. Dayrit, Lolita G. Lagurin, John Daniel J. Magsalin, Anthony R. Zosa
Chemical Profiling And Chemical Standardization Of Vitex Negundo Using 13c Nmr, Fabian M. Dayrit, Lolita G. Lagurin, John Daniel J. Magsalin, Anthony R. Zosa
Chemistry Faculty Publications
Chemical profiling and standardization of the defatted methanol extract of the leaves of Vitex negundo L. were carried out using 13C nuclear magnetic resonance (NMR) analysis followed by chemometric analysis of the chemical shift data. Chemical profile was obtained using a k-means cluster profile and chemical standardization which was achieved using a multivariate control chart. The V. negundo samples were made up of four groups: the training set, submitted samples from production farms, commercial samples, such as tablets, capsules and teas, and experimental samples (samples which were allowed to degrade). Four groups were generated in k-means cluster, which generally corresponded …
Myeloperoxidase-Mediated Protein Lysine Oxidation Generates 2- Aminoadipic Acid And Lysine Nitrile In Vivo, Hongqiao Lin, Bruce S. Levison, Jennifer A. Buffa, Ying Huang, Xiaoming Fu, Zeneng Wang, Valentin Gogonea, Joseph A. Didonato, Stanley L. Hazen
Myeloperoxidase-Mediated Protein Lysine Oxidation Generates 2- Aminoadipic Acid And Lysine Nitrile In Vivo, Hongqiao Lin, Bruce S. Levison, Jennifer A. Buffa, Ying Huang, Xiaoming Fu, Zeneng Wang, Valentin Gogonea, Joseph A. Didonato, Stanley L. Hazen
Chemistry Faculty Publications
Recent studies reveal 2-aminoadipic acid (2-AAA) is both elevated in subjects at risk for diabetes and mechanistically linked to glucose homeostasis. Prior studies also suggest enrichment of protein-bound 2-AAA as an oxidative post-translational modification of lysyl residues in tissues associated with degenerative diseases of aging. While in vitro studies suggest redox active transition metals or myeloperoxidase (MPO) generated hypochlorous acid (HOCl) may produce protein-bound 2-AAA, the mechanism(s) responsible for generation of 2- AAA during inflammatory diseases are unknown. In initial studies we observed that traditional acid- or basecatalyzed protein hydrolysis methods previously employed to measure tissue 2-AAA can artificially generate …
A Mutation In Ltbp2 Causes Congenital Glaucoma In Domestic Cats (Felis Catus), Markus H. Kuehn, Koren A. Lipsett, Marilyn Menotti-Raymond, S. Scott Whitmore, Todd E. Scheetz, Victor A. David, Stephen J. O'Brien, Zhongyuan Zhao, Jackie K. Jens, Elizabeth M. Snella, N. Matthew Ellinwood, Gillian J. Mclellan
A Mutation In Ltbp2 Causes Congenital Glaucoma In Domestic Cats (Felis Catus), Markus H. Kuehn, Koren A. Lipsett, Marilyn Menotti-Raymond, S. Scott Whitmore, Todd E. Scheetz, Victor A. David, Stephen J. O'Brien, Zhongyuan Zhao, Jackie K. Jens, Elizabeth M. Snella, N. Matthew Ellinwood, Gillian J. Mclellan
Chemistry Faculty Publications
The glaucomas are a group of diseases characterized by optic nerve damage that together represent a leading cause of blindness in the human population and in domestic animals. Here we report a mutation in LTBP2 that causes primary congenital glaucoma (PCG) in domestic cats. We identified a spontaneous form of PCG in cats and established a breeding colony segregating for PCG consistent with fully penetrant, autosomal recessive inheritance of the trait. Elevated intraocular pressure, globe enlargement and elongated ciliary processes were consistently observed in all affected cats by 8 weeks of age. Varying degrees of optic nerve damage resulted by …
Photocatalytic Reduction Of Fumarate To Succinate On Zns Mineral Surfaces, Ruixin Zhou, Marcelo I. Guzman
Photocatalytic Reduction Of Fumarate To Succinate On Zns Mineral Surfaces, Ruixin Zhou, Marcelo I. Guzman
Chemistry Faculty Publications
The reductive tricarboxylic acid (rTCA) cycle is an important central biosynthetic pathway that fixes CO2 into carboxylic acids. Among the five reductive steps in the rTCA cycle, the two-electron reduction of fumarate to succinate proceeds nonenzymatically on the surface of photoexcited sphalerite (ZnS) colloids suspended in water. This model reaction is chosen to systematically study the surface photoprocess occurring on ZnS in the presence of [Na2S] (1–10 mM) hole scavenger at 15 °C. Experiments at variable pH (5–10) indicate that monodissociated fumaric acid is the primary electron acceptor forming the monoprotic form of succinic acid. The following …
Metabolomics Reveals New Mechanisms For Pathogenesis In Barth Syndrome And Introduces Novel Roles For Cardiolipin In Cellular Function, Yana Sandlers, Kelly Mercier, Wimal Pathmasiri, Jim Carlson, Susan Mcritchie, Susan Sumner, Hilary J. Vernon
Metabolomics Reveals New Mechanisms For Pathogenesis In Barth Syndrome And Introduces Novel Roles For Cardiolipin In Cellular Function, Yana Sandlers, Kelly Mercier, Wimal Pathmasiri, Jim Carlson, Susan Mcritchie, Susan Sumner, Hilary J. Vernon
Chemistry Faculty Publications
Barth Syndrome is the only known Mendelian disorder of cardiolipin remodeling, with characteristic clinical features of cardiomyopathy, skeletal myopathy, and neutropenia. While the primary biochemical defects of reduced mature cardiolipin and increased monolysocardiolipin are well-described, much of the downstream biochemical dysregulation has not been uncovered, and biomarkers are limited. In order to further expand upon the knowledge of the biochemical abnormalities in Barth Syndrome, we analyzed metabolite profiles in plasma from a cohort of individuals with Barth Syndrome compared to age-matched controls via 1H nuclear magnetic resonance spectroscopy and liquid chromatography-mass spectrometry. A clear distinction between metabolite profiles of …
The Dual Regulatory Role Of Amino Acids Leu480 And Gln481 Of Prothrombin, Joesph R. Wiencek, Jamila Hirbawi, Vivien C. Yee, Michael Kalafatis
The Dual Regulatory Role Of Amino Acids Leu480 And Gln481 Of Prothrombin, Joesph R. Wiencek, Jamila Hirbawi, Vivien C. Yee, Michael Kalafatis
Chemistry Faculty Publications
Prothrombin (FII) is activated to α-thrombin (IIa) by prothrombinase. Prothrombinase is composed of a catalytic subunit, factor Xa (fXa), and a regulatory subunit, factor Va (fVa), assembled on a membrane surface in the presence of divalent metal ions. We constructed, expressed, and purified several mutated recombinant FII (rFII) molecules within the previously determined fVa-dependent binding site for fXa (amino acid region 473–487 of FII). rFII molecules bearing overlapping deletions within this significant region first established the minimal stretch of amino acids required for the fVa-dependent recognition exosite for fXa in prothrombinase within the amino acid sequence Ser478–Val479 …
It Is All About (U)Biquitin: Role Of Altered Ubiquitin-Proteasome System And Uchl1 In Alzheimer Disease, Antonella Tramutola, Fabio Di Domenico, Eugenio Barone, Marzia Perluigi, D. Allan Butterfield
It Is All About (U)Biquitin: Role Of Altered Ubiquitin-Proteasome System And Uchl1 In Alzheimer Disease, Antonella Tramutola, Fabio Di Domenico, Eugenio Barone, Marzia Perluigi, D. Allan Butterfield
Chemistry Faculty Publications
Free radical-mediated damage to macromolecules and the resulting oxidative modification of different cellular components are a common feature of aging, and this process becomes much more pronounced in age-associated pathologies, including Alzheimer disease (AD). In particular, proteins are particularly sensitive to oxidative stress-induced damage and these irreversible modifications lead to the alteration of protein structure and function. In order to maintain cell homeostasis, these oxidized/damaged proteins have to be removed in order to prevent their toxic accumulation. It is generally accepted that the age-related accumulation of “aberrant” proteins results from both the increased occurrence of damage and the decreased efficiency …
Multi-Dimensional Glycan Microarrays With Glyco-Macroligands, Satya Nandana Narla, Huan Nie, Yu Li, Xue-Long Sun
Multi-Dimensional Glycan Microarrays With Glyco-Macroligands, Satya Nandana Narla, Huan Nie, Yu Li, Xue-Long Sun
Chemistry Faculty Publications
Glycan microarray has become a powerful high-throughput tool for examining binding interactions of carbohydrates with the carbohydrate binding biomolecules like proteins, enzymes, antibodies etc. It has shown great potential for biomedical research and applications, such as antibody detection and profiling, vaccine development, biomarker discovery, and drug screening. Most glycan microarrays were made with monovalent glycans immobilized directly onto the array surface via either covalent or non-covalent bond, which afford a multivalent glycans in two dimensional (2D) displaying. A variety of glyco-macroligands have been developed to mimic multivalent carbohydrate-protein interactions for studying carbohydrate-protein interactions and biomedical research and applications. Recently, a …
Heterogeneous Oxidation Of Catechol, Elizabeth A. Pillar, Ruixin Zhou, Marcelo I. Guzman
Heterogeneous Oxidation Of Catechol, Elizabeth A. Pillar, Ruixin Zhou, Marcelo I. Guzman
Chemistry Faculty Publications
Natural and anthropogenic emissions of aromatic hydrocarbons from biomass burning, agro-industrial settings, and fossil fuel combustion contribute precursors to secondary aerosol formation (SOA). How these compounds are processed under humid tropospheric conditions is the focus of current attention to understand their environmental fate. This work shows how catechol thin films, a model for oxygenated aromatic hydrocarbons present in biomass burning and combustion aerosols, undergo heterogeneous oxidation at the air–solid interface under variable relative humidity (RH = 0–90%). The maximum reactive uptake coefficient of O3(g) by catechol γO3 = (7.49 ± 0.35) × 10–6 occurs for …
Reclaiming The Efficacy Of Β-Lactam–Β-Lactamase Inhibitor Combinations: Avibactam Restores The Susceptibility Of Cmy-2-Producing Escherichia Coli To Ceftazidime, Krisztina M. Papp-Wallace, Marisa L. Winkler, Julian A. Gatta, Magdalena A. Taracila, Sujatha Chilakala, Yan Xu, J. Kristie Johnson, Robert A. Bonomo
Reclaiming The Efficacy Of Β-Lactam–Β-Lactamase Inhibitor Combinations: Avibactam Restores The Susceptibility Of Cmy-2-Producing Escherichia Coli To Ceftazidime, Krisztina M. Papp-Wallace, Marisa L. Winkler, Julian A. Gatta, Magdalena A. Taracila, Sujatha Chilakala, Yan Xu, J. Kristie Johnson, Robert A. Bonomo
Chemistry Faculty Publications
CMY-2 is a plasmid-encoded Ambler class C cephalosporinase that is widely disseminated in Enterobacteriaceae and is responsible for expanded-spectrum cephalosporin resistance. As a result of resistance to both ceftazidime and β-lactamase inhibitors in strains carrying blaCMY, novel β-lactam–β-lactamase inhibitor combinations are sought to combat this significant threat to β-lactam therapy. Avibactam is a bridged diazabicyclo [3.2.1]octanone non-β-lactam β-lactamase inhibitor in clinical development that reversibly inactivates serine β-lactamases. To define the spectrum of activity of ceftazidime-avibactam, we tested the susceptibilities of Escherichia coli clinical isolates that carry blaCMY-2 or blaCMY-69 and investigated the inactivation kinetics of CMY-2. Our analysis showed that …
Bsa–Boronic Acid Conjugate As Lectin Mimetics, Satya Nandana Narla, Poornima Pinnamaneni, Huan Nie, Yu Li, Xue-Long Sun
Bsa–Boronic Acid Conjugate As Lectin Mimetics, Satya Nandana Narla, Poornima Pinnamaneni, Huan Nie, Yu Li, Xue-Long Sun
Chemistry Faculty Publications
We report bovine serum albumin (BSA)–boronic acid (BA) conjugates as lectin mimetics and their glyco-capturing capacity. The BSA–BA conjugates were synthesized by amidation of carboxylic acid groups in BSA with aminophenyl boronic acid in the presence of EDC, and were characterized by Alizarin Red S (ARS) assay and SDS–PAGE gel. The BSA–BA conjugates were immobilized onto maleimide-functionalized silica beads and their sugar capturing capacity and specificity were confirmed by ARS displacement assay. Further, surface plasmon resonance (SPR) analysis of the glyco-capturing activity of the BSA–BA conjugates was conducted by immobilizing BSA–BA onto SPR gold chip. Overall, we demonstrated a BSA–BA-based …
Quantification Of Free Sialic Acid In Human Plasma Through A Robust Quinoxalinone Derivatization And Lc–Ms/Ms Using Isotope-Labeled Standard Calibration, Dan Wang, Xiang Zhou, Lin Wang, Sihe Wang, Xue-Long Sun
Quantification Of Free Sialic Acid In Human Plasma Through A Robust Quinoxalinone Derivatization And Lc–Ms/Ms Using Isotope-Labeled Standard Calibration, Dan Wang, Xiang Zhou, Lin Wang, Sihe Wang, Xue-Long Sun
Chemistry Faculty Publications
We report an accurate quantification of free sialic acid (SA) in human plasma using LC–MS/MS method with isotope-labeled standard calibration (ILSC) and robust derivatization. Specifically, derivatization of SA with a stable and inexpensive 3,4-diaminotoluene (DAT) provides a stable product of SA with high MS response, proving a convenient and cost-effective LC–MS/MS analysis of free SA. In addition, the use of 13C3-SA as calibration standard ensured the accuracy for the measurement. This assay used ultra high performance liquid chromatography (UHPLC) for separation of native/labeled SA and IS from matrix interference, and employed mass spectrometry in multiple reaction monitoring …
A Loose Domain Swapping Organization Confers A Remarkable Stability To The Dimeric Structure Of The Arginine Binding Protein From Thermotoga Maritima, Alessia Ruggiero, Jonathan D. Dattelbaum, Maria Staiano, Rita Berisio, Sabato D'Auria, Luigi Vitagliano
A Loose Domain Swapping Organization Confers A Remarkable Stability To The Dimeric Structure Of The Arginine Binding Protein From Thermotoga Maritima, Alessia Ruggiero, Jonathan D. Dattelbaum, Maria Staiano, Rita Berisio, Sabato D'Auria, Luigi Vitagliano
Chemistry Faculty Publications
The arginine binding protein from Thermatoga maritima (TmArgBP), a substrate binding protein (SBP) involved in the ABC system of solute transport, presents a number of remarkable properties. These include an extraordinary stability to temperature and chemical denaturants and the tendency to form multimeric structures, an uncommon feature among SBPs involved in solute transport. Here we report a biophysical and structural characterization of the TmArgBP dimer. Our data indicate that the dimer of the protein is endowed with a remarkable stability since its full dissociation requires high temperature as well as SDS and urea at high concentrations. In order to elucidate …
Insights Into The Roles Of Desolvation And Π-Electron Interactions During Dna Polymerization, Edward A. Motea, Irene Lee, Anthony J. Berdis
Insights Into The Roles Of Desolvation And Π-Electron Interactions During Dna Polymerization, Edward A. Motea, Irene Lee, Anthony J. Berdis
Chemistry Faculty Publications
This report describes the use of several isosteric non-natural nucleotides as probes to evaluate the roles of nucleobase shape, size, solvation energies, and π-electron interactions as forces influencing key kinetic steps of the DNA polymerization cycle. Results are provided using representative high- and low-fidelity DNA polymerases. Results generated with the E. coli Klenow fragment reveal that this high-fidelity polymerase utilizes hydrophobic nucleotide analogues with higher catalytic efficiencies compared to hydrophilic analogues. These data support a major role for nucleobase desolvation during nucleotide selection and insertion. In contrast, the low-fidelity HIV-1 reverse transcriptase discriminates against hydrophobic analogues and only tolerates non-natural …
Spectroscopic Analysis Of Polymerization And Exonuclease Proofreading By A High-Fidelity Dna Polymerase During Translesion Dna Synthesis, Babho Devadoss, Irene Lee, Anthony J. Berdis
Spectroscopic Analysis Of Polymerization And Exonuclease Proofreading By A High-Fidelity Dna Polymerase During Translesion Dna Synthesis, Babho Devadoss, Irene Lee, Anthony J. Berdis
Chemistry Faculty Publications
High fidelity DNA polymerases maintain genomic fidelity through a series of kinetic steps that include nucleotide binding, conformational changes, phosphoryl transfer, polymerase translocation, and nucleotide excision. Developing a comprehensive understanding of how these steps are coordinated during correct and pro-mutagenic DNA synthesis has been hindered due to lack of spectroscopic nucleotides that function as efficient polymerase substrates. This report describes the application of a non-natural nucleotide designated 5-naphthyl-indole-2′-deoxyribose triphosphate which behaves as a fluorogenic substrate to monitor nucleotide incorporation and excision during the replication of normal DNA versus two distinct DNA lesions (cyclobutane thymine dimer and an abasic site). Transient …
Periplasmic Binding Proteins In Thermophiles: Characterization And Potential Application Of An Arginine-Binding Protein From Thermotoga Maritima: A Brief Thermo-Story, Alessio Ausili, Maria Staiano, Jonathan D. Dattelbaum, Antonio Varriale, Alessandro Capo, Sabato D'Auria
Periplasmic Binding Proteins In Thermophiles: Characterization And Potential Application Of An Arginine-Binding Protein From Thermotoga Maritima: A Brief Thermo-Story, Alessio Ausili, Maria Staiano, Jonathan D. Dattelbaum, Antonio Varriale, Alessandro Capo, Sabato D'Auria
Chemistry Faculty Publications
Arginine-binding protein from the extremophile Thermotoga maritima is a 27.7 kDa protein possessing the typical two-domain structure of the periplasmic binding proteins family. The protein is characterized by a very high specificity and affinity to bind to arginine, also at high temperatures. Due to its features, this protein could be taken into account as a potential candidate for the design of a biosensor for arginine. It is important to investigate the stability of proteins when they are used for biotechnological applications. In this article, we review the structural and functional features of an arginine-binding protein from the extremophile Thermotoga maritima …
Structurally Diverse Hamigerans From The New Zealand Marine Sponge Hamigera Tarangaensis: Nmr-Directed Isolation, Structure Elucidation And Antifungal Activity, A. Jonathan Singh, Jonathan D. Dattelbaum, Jessica J. Field, Zlatka Smart, Ethan F. Woolly, Jacqueline M. Barber, Rosemary Heathcott, John H. Miller, Peter T. Northcote
Structurally Diverse Hamigerans From The New Zealand Marine Sponge Hamigera Tarangaensis: Nmr-Directed Isolation, Structure Elucidation And Antifungal Activity, A. Jonathan Singh, Jonathan D. Dattelbaum, Jessica J. Field, Zlatka Smart, Ethan F. Woolly, Jacqueline M. Barber, Rosemary Heathcott, John H. Miller, Peter T. Northcote
Chemistry Faculty Publications
The NMR-directed investigation of the New Zealand marine sponge Hamigera tarangaensis has afforded ten new compounds of the hamigeran family, and a new 13-epi-verrucosane congener. Notably, hamigeran F (6) possesses an unusual carbon–carbon bond between C-12 and C-13, creating an unprecedented skeleton within this class. In particular, the structural features of 6, hamigeran H (10) and hamigeran J (12) imply a diterpenoid origin, which has allowed the putative biogenesis of three hamigeran carbon skeletons to be proposed based on geranyl geranyl pyrophosphate. All new hamigerans exhibited micromolar activity towards the HL-60 …
Voltage-Controlled Enzyme-Catalyzed Glucose–Gluconolactone Conversion Using A Field-Effect Enzymatic Detector, Siu Tung Yau, Yan Xu, Yang Song, Ye Feng, Jiapeng Wang
Voltage-Controlled Enzyme-Catalyzed Glucose–Gluconolactone Conversion Using A Field-Effect Enzymatic Detector, Siu Tung Yau, Yan Xu, Yang Song, Ye Feng, Jiapeng Wang
Chemistry Faculty Publications
The field-effect enzymatic detection (FEED) technique was used to control the kinetics of the enzymatic conversion of glucose to gluconolactone. The glucose–gluconolactone conversion occurring at an enzyme-immobilized electrode, a well-studied process, was confirmed using mass spectrometry. Electrochemical studies showed that the glucose oxidation current depends on the gating voltage VG and the ion concentration of the sample solution. Additionally, the depletion of glucose in the sample also showed a dependence on VG. FEED was used to detect H2O2 on the zepto-molar level in order to show the ultrasensitive detection capability of the technique. These results, while providing evidence for the …
Exploring The Role Of A Conserved Class A Residue In The Ω-Loop Of Kpc-2 Β-Lactamase: A Mechanism For Ceftazidime Hydrolysis
Chemistry Faculty Publications
Gram-negative bacteria harboring KPC-2, a class A β-lactamase, are resistant to all β-lactam antibiotics and pose a major public health threat. Arg-164 is a conserved residue in all class A β-lactamases and is located in the solvent-exposed Ω-loop of KPC-2. To probe the role of this amino acid in KPC-2, we performed site-saturation mutagenesis. When compared with wild type, 11 of 19 variants at position Arg-164 in KPC-2 conferred increased resistance to the oxyimino-cephalosporin, ceftazidime (minimum inhibitory concentration; 32→128 mg/liter) when expressed in Escherichia coli. Using the R164S variant of KPC-2 as a representative β-lactamase for more detailed analysis, we …
Understanding The Molecular Determinants Of Substrate And Inhibitor Specificities In The Carbapenemase Kpc-2: Exploring The Roles Of Arg220 And Glu276
Chemistry Faculty Publications
β-Lactamases are important antibiotic resistance determinants expressed by bacteria. By studying the mechanistic properties of β-lactamases, we can identify opportunities to circumvent resistance through the design of novel inhibitors. Comparative amino acid sequence analysis of class A β-lactamases reveals that many enzymes possess a localized positively charged residue (e.g., R220, R244, or R276) that is critical for interactions with β-lactams and β-lactamase inhibitors. To better understand the contribution of these residues to the catalytic process, we explored the roles of R220 and E276 in KPC-2, a class A β-lactamase that inactivates carbapenems and β-lactamase inhibitors. Our study reveals that substitutions …
Development Of A ‘Clickable’ Non-Natural Nucleotide To Visualize The Replication Of Non-Instructional Dna Lesions, Edward A. Motea, Irene Lee, Anthony J. Berdis
Development Of A ‘Clickable’ Non-Natural Nucleotide To Visualize The Replication Of Non-Instructional Dna Lesions, Edward A. Motea, Irene Lee, Anthony J. Berdis
Chemistry Faculty Publications
The misreplication of damaged DNA is an important biological process that produces numerous adverse effects on human health. This report describes the synthesis and characterization of a non-natural nucleotide, designated 3-ethynyl-5-nitroindolyl-2′-deoxyriboside triphosphate (3-Eth-5-NITP), as a novel chemical reagent that can probe and quantify the misreplication of damaged DNA. We demonstrate that this non-natural nucleotide is efficiently inserted opposite an abasic site, a commonly formed and potentially mutagenic non-instructional DNA lesion. The strategic placement of the ethynyl moiety allows the incorporated nucleoside triphosphate to be selectively tagged with an azide-containing fluorophore using ‘click’ chemistry. This reaction provides a facile way to …
Removal Of Uracil By Uracil Dna Glycosylase Limits Pemetrexed Cytotoxicity: Overriding The Limit With Methoxyamine To Inhibit Base Excision Repair, A. D. Bulgar, L. D. Weeks, Y. Miao, S. Yang, Yan Xu, C. Guo, S. Markowitz, N. Oleinick, S. L. Gerson, Lili Liu
Removal Of Uracil By Uracil Dna Glycosylase Limits Pemetrexed Cytotoxicity: Overriding The Limit With Methoxyamine To Inhibit Base Excision Repair, A. D. Bulgar, L. D. Weeks, Y. Miao, S. Yang, Yan Xu, C. Guo, S. Markowitz, N. Oleinick, S. L. Gerson, Lili Liu
Chemistry Faculty Publications
Uracil DNA glycosylase (UDG) specifically removes uracil bases from DNA, and its repair activity determines the sensitivity of the cell to anticancer agents that are capable of introducing uracil into DNA. In the present study, the participation of UDG in the response to pemetrexed-induced incorporation of uracil into DNA was studied using isogenic human tumor cell lines with or without UDG (UDG+/+/UDG−/−). UDG−/− cells were very sensitive to pemetrexed. Cell killing by pemetrexed was associated with genomic uracil accumulation, stalled DNA replication, and catastrophic DNA strand breaks. By contrast, UDG+/+ cells were >10 times more resistant to pemetrexed due to …
Exploring The Roles Of Nucleobase Desolvation And Shape Complementarity During The Misreplication Of O6-Methylguanine, Delia Chavarria, Andrea Ramos Serrano, Ichiro Hirao, Anthony J. Berdis
Exploring The Roles Of Nucleobase Desolvation And Shape Complementarity During The Misreplication Of O6-Methylguanine, Delia Chavarria, Andrea Ramos Serrano, Ichiro Hirao, Anthony J. Berdis
Chemistry Faculty Publications
O6-methylguanine is a miscoding DNA lesion arising from the alkylation of guanine. This report uses the bacteriophage T4 DNA polymerase as a model to probe the roles hydrogen-bonding interactions, shape/size, and nucleobase desolvation during the replication of this miscoding lesion. This was accomplished by using transient kinetic techniques to monitor the kinetic parameters for incorporating and extending natural and non-natural nucleotides. In general, the efficiency of nucleotide incorporation does not depend on the hydrogen-bonding potential of the incoming nucleotide. Instead, nucleobase hydrophobicity and shape complementarity appear to be the preeminent factors controlling nucleotide incorporation. In addition, shape complementarity plays a …
The Exonuclease Activity Of Hpmc2 Is Required For Transcriptional Regulation Of The Qr Gene And Repair Of Estrogen-Induced Abasic Sites, N. Krishnamurthy, C. R. Ngam, Anthony J. Berdis, M. M. Montano
The Exonuclease Activity Of Hpmc2 Is Required For Transcriptional Regulation Of The Qr Gene And Repair Of Estrogen-Induced Abasic Sites, N. Krishnamurthy, C. R. Ngam, Anthony J. Berdis, M. M. Montano
Chemistry Faculty Publications
We have previously reported that the expression of antioxidative stress enzymes is upregulated by trans-hydroxytamoxifen (TOT) in breast epithelial cell lines providing protection against estrogen-induced DNA damage. This regulation involves Estrogen Receptor β (ERβ) recruitment to the Electrophile Response Element (EpRE) and a novel protein, human homolog of Xenopus gene which Prevents Mitotic Catastrophe (hPMC2). We have also demonstrated that ERβ and hPMC2 are required for TOT-dependent recruitment of poly (ADP-ribose) polymerase 1 (PARP-1) and Topoisomerase IIβ (Topo IIβ) to the EpRE. Sequence analysis reveals that the C-terminus of hPMC2 encodes a putative exonuclease domain. Using in vitro kinetic assays, …
Epistatic Roles For Pseudomonas Aeruginosa Muts And Dinb (Dna Pol Iv) In Coping With Reactive Oxygen Species-Induced Dna Damage, Laurie H. Sanders, Babho Devadoss, Geraldine V. Raja, Jaime O'Connor, Shengchang Su, Daniel J. Wozniak, Daniel J. Hassett, Anthony J. Berdis, Mark D. Sutton
Epistatic Roles For Pseudomonas Aeruginosa Muts And Dinb (Dna Pol Iv) In Coping With Reactive Oxygen Species-Induced Dna Damage, Laurie H. Sanders, Babho Devadoss, Geraldine V. Raja, Jaime O'Connor, Shengchang Su, Daniel J. Wozniak, Daniel J. Hassett, Anthony J. Berdis, Mark D. Sutton
Chemistry Faculty Publications
Pseudomonas aeruginosa is especially adept at colonizing the airways of individuals afflicted with the autosomal recessive disease cystic fibrosis (CF). CF patients suffer from chronic airway inflammation, which contributes to lung deterioration. Once established in the airways, P. aeruginosa continuously adapts to the changing environment, in part through acquisition of beneficial mutations via a process termed pathoadaptation. MutS and DinB are proposed to play opposing roles in P. aeruginosa pathoadaptation: MutS acts in replication-coupled mismatch repair, which acts to limit spontaneous mutations; in contrast, DinB (DNA polymerase IV) catalyzes error-prone bypass of DNA lesions, contributing to mutations. As part of …
Her2 Targeted Molecular Mr Imaging Using A De Novo Designed Protein Contrast Agent, Jingjuan Qiao, Shunyi Li, Lixia Wei, Jie Jiang, Robert Long, Hui Mao, Ling Wei, Liya Wang, Hua Yang, Hans E. Grossniklaus, Zhi-Ren Liu, Jenny J. Yang
Her2 Targeted Molecular Mr Imaging Using A De Novo Designed Protein Contrast Agent, Jingjuan Qiao, Shunyi Li, Lixia Wei, Jie Jiang, Robert Long, Hui Mao, Ling Wei, Liya Wang, Hua Yang, Hans E. Grossniklaus, Zhi-Ren Liu, Jenny J. Yang
Chemistry Faculty Publications
The application of magnetic resonance imaging (MRI) to non-invasively assess disease biomarkers has been hampered by the lack of desired contrast agents with high relaxivity, targeting capability, and optimized pharmacokinetics. We have developed a novel MR imaging probe targeting to HER2, a biomarker for various cancer types and a drug target for anti-cancer therapies. This multimodal HER20targeted MR imaging probe integrates a de novo designed protein contrast agent with a high affinity HER2 affibody and a near IR fluorescent dye. Our probe can differentially monitor tumors with different expression levels of HER2 in both human cell lines and xenograft mice …
Quantifying The Energetic Contributions Of Desolvation And Π-Electron Density During Translesion Dna Synthesis, Edward A. Motea, Irene Lee, Anthony J. Berdis
Quantifying The Energetic Contributions Of Desolvation And Π-Electron Density During Translesion Dna Synthesis, Edward A. Motea, Irene Lee, Anthony J. Berdis
Chemistry Faculty Publications
This report examines the molecular mechanism by which high-fidelity DNA polymerases select nucleotides during the replication of an abasic site, a non-instructional DNA lesion. This was accomplished by synthesizing several unique 5-substituted indolyl 2′-deoxyribose triphosphates and defining their kinetic parameters for incorporation opposite an abasic site to interrogate the contributions of π-electron density and solvation energies. In general, the Kd, app values for hydrophobic non-natural nucleotides are ∼10-fold lower than those measured for isosteric hydrophilic analogs. In addition, kpol values for nucleotides that contain less π-electron densities are slower than isosteric analogs possessing higher degrees of π-electron density. The differences …
Crystallization And Preliminary X-Ray Crystallographic Analysis Of Ligand-Free And Arginine-Bound Forms Of Thermotoga Maritima Arginine-Binding Protein, Alessia Ruggiero, Jonathan D. Dattelbaum, Anna Pennacchio, Luisa Iozzion, Maria Staiano, Matthew S. Luchansky, Bryan S. Der, Rita Berisio, Sabato D'Auria, Luigi Vitagliano
Crystallization And Preliminary X-Ray Crystallographic Analysis Of Ligand-Free And Arginine-Bound Forms Of Thermotoga Maritima Arginine-Binding Protein, Alessia Ruggiero, Jonathan D. Dattelbaum, Anna Pennacchio, Luisa Iozzion, Maria Staiano, Matthew S. Luchansky, Bryan S. Der, Rita Berisio, Sabato D'Auria, Luigi Vitagliano
Chemistry Faculty Publications
The arginine-binding protein from Thermotoga maritima (TmArgBP) is an arginine-binding component of the ATP-binding cassette (ABC) transport system in this hyperthermophilic bacterium. This protein is endowed with an extraordinary stability towards thermal and chemical denaturation. Its structural characterization may provide useful insights for the clarification of structure– stability relationships and for the design of new biosensors. Crystallization trials were set up for both arginine-bound and ligand-free forms of TmArgBP and crystals suitable for crystallographic investigations were obtained for both forms. Ordered crystals of the arginine adduct of TmArgBP could only be obtained by using the detergent LDAO as an additive …