Bacteriostatic Effects Of Sucralose On Environmental Bacteria,
2013
University of North Florida
Bacteriostatic Effects Of Sucralose On Environmental Bacteria, Arthur Phillip Omran Jr.
UNF Graduate Theses and Dissertations
Sucralose is a zero calorie sweetener developed and manufactured by Tate and Lyle Sweetener Company in the 1980’s. They sell the sweetener compounded with maltodextrin and dextrose under the brand name Splenda®. Sucralose was developed as a low cost artificial sweetener that is non-metabolizable in humans and can withstand changes in pH and temperature. It is not degraded by the waste water treatment process. Since the molecule can withstand heat, acidification and microbial degradation it is accumulating in the environment, and has been found in waste water, estuaries, rivers and the Gulf Stream. The highest concentration of environmental sucralose detected …
Sequencing A Dna Polymerase Alpha Gene In Thermomyces Lanuginosus,
2013
University of Northern Iowa
Sequencing A Dna Polymerase Alpha Gene In Thermomyces Lanuginosus, Sonia Tien-Yang Han
Honors Program Theses
DNA polymerases are present in all living organisms and it is expected that there should be a reasonable degree of conservation, or similarity in how the polymerases function, between species. This makes the possibility of developing treatments using DNA polymerase more likely, as the treatment would not necessarily depend on using human DNA as the base material, which would be more expensive. However, this cannot be known unless there is a reasonable number of DNA sequences available from multiple species to analyze. This is a growing research, but the majority of sequences known are from mammals. Currently there is very …
Expressed Sequence Tag For Dna Polymerase Alpha In Embryonic Chicken Brain,
2013
University of Northern Iowa
Expressed Sequence Tag For Dna Polymerase Alpha In Embryonic Chicken Brain, Rebecca Krewer
Honors Program Theses
Replicative DNA polymerases are enzymes located in the nuclei of cells. They have a role in the control of DNA synthesis in all cells, and problems with their function and control affect cell growth. One of these polymerases, DNA polymerase alpha ("pol α"), is a possible point of control for cell growth because it initiates DNA synthesis. The ability to selectively turn on or shut off this polymerase in cells could provide answers to problems ranging from cancer's unregulated growth to regeneration of tissues. However, control mechanisms for DNA pol α are not fully understood at this time. The central …
Intensity-Based Skeletonization Of Cryoem Gray-Scale Images Using A True Segmentation-Free Algorithm,
2013
Old Dominion University
Intensity-Based Skeletonization Of Cryoem Gray-Scale Images Using A True Segmentation-Free Algorithm, Kamal Al Nasr, Chunmei Liu, Mugizi Rwebangira, Legand Burge, Jing He
Computer Science Faculty Publications
Cryo-electron microscopy is an experimental technique that is able to produce 3D gray-scale images of protein molecules. In contrast to other experimental techniques, cryo-electron microscopy is capable of visualizing large molecular complexes such as viruses and ribosomes. At medium resolution, the positions of the atoms are not visible and the process cannot proceed. The medium-resolution images produced by cryo-electron microscopy are used to derive the atomic structure of the proteins in de novo modeling. The skeletons of the 3D gray-scale images are used to interpret important information that is helpful in de novo modeling. Unfortunately, not all features of the …
Periplasmic Binding Proteins In Thermophiles: Characterization And Potential Application Of An Arginine-Binding Protein From Thermotoga Maritima: A Brief Thermo-Story,
2013
University of Richmond
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,
2013
University of Richmond
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 …
Solid-Phase Organic Matter Reduction Regulates Anaerobic Decomposition In Bog Soil,
2013
Chapman University
Solid-Phase Organic Matter Reduction Regulates Anaerobic Decomposition In Bog Soil, Jason K. Keller, Kimberly K. Takagi
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Peatlands store globally significant amounts of carbon and are important sources of the greenhouse gas methane (CH4) to the atmosphere. However, for reasons which are not well understood, many peatland soils produce smaller amounts of CH4 than theoretically predicted, and carbon dioxide (CO2) produced during anaerobic decomposition in peatland soils cannot be accounted for by commonly measured microbial processes. Here we show that the reduction of solid-phase organic matter (i.e., humic substances) suppresses CH4 production in a bog soil and can be responsible for 33–61% of the total carbon mineralization in this soil. These results demonstrate that the reduction of …
The Cave Environment Influencing The Lipid Profile And Hepatic Lipogenesis Of The Fish Ancistrus Cryptophthalmus Reis, 1987 (Siluriformes: Loricariidae),
2013
Universidade Federal de Lavras
The Cave Environment Influencing The Lipid Profile And Hepatic Lipogenesis Of The Fish Ancistrus Cryptophthalmus Reis, 1987 (Siluriformes: Loricariidae), Valquíria Aparecida Alves Bastos, Rodrigo Lopes Ferreira, Daniel Cardoso Carvalho, Marina Lages Pugedo, Luciana De Matos Alves Pinto
International Journal of Speleology
The metabolism of hypogean organisms is frequently molded by the cave environment traits, especially food scarcity. The aim of the present work was to evaluate the influence of such environment on lipid composition and hepatic lipogenesis in the fish Ancistrus cryptophthalmus. For this, the species was compared to an epigean population of the same species. A greater accumulation of total lipids was observed in the cave-dwelling fish (18.36 g/100 g tissue) compared to the surface fish (14.09 g/100 g tissue). The muscle fatty acid profile also varied between the populations. Arachidonic acid was only detected in the epigean fish, while …
Decoration Of Graphene With Metal Nanoparticles And Its Application For Bioanalysis,
2013
Montclair State University
Decoration Of Graphene With Metal Nanoparticles And Its Application For Bioanalysis, Keun Soo Kwon
Theses, Dissertations and Culminating Projects
Graphene is a two-dimensional monolayer of tightly packed sp2 hybridized Carbon atoms. Formed from graphite, the theoretical surface area of the monolayer is about 2630 m2/g, and the initial formation of graphene oxide from graphite oxide introduces a variety o f functional groups, such as -COOH, -C=0, and -OH, on its surface. The high surface area and the rich presence of functional groups, along with the potential formation o f sp2 bonding networks within graphene oxide, all serve as critical factors allowing for additional chemical modifications. There are extensive research attempts being performed to explore and …
Polyphenoloxidase And Perioxidase Activity During Open Air Ripening Storage Of Pineapple (Ananas Comosus L.), Mango (Mangifera Indica) And Papaya (Carica Papaya) Fruits Grown In Dar Es Salaam, Tanzania,
2012
Chemistry Department, University of Dar es Salaam, P. O. Box 35061 Dar es Salaam, Tanzania
Polyphenoloxidase And Perioxidase Activity During Open Air Ripening Storage Of Pineapple (Ananas Comosus L.), Mango (Mangifera Indica) And Papaya (Carica Papaya) Fruits Grown In Dar Es Salaam, Tanzania, Oc Othman
Tanzania Journal of Science
Polyphenoloxidase (PPO) and perioxidase (POD), the enzymes responsible for causing browning and change in texture and flavor of fruits and vegetables, were extracted and measured in harvested mature pineapple (Ananas comosus L.), mango (Mangifera indica) (Viringe and Dodo varieties) and papaya (Carica papaya) fruits during off vine, open air, room temperature ripening storage. The initial (at harvest) average PPO activity values in Δ Optical Density (OD) per minute per cm3 of enzyme solution were 0.00074, 0.00083 and 0.0010 for early, mid and late season pineapple fruits respectively. The initial average PPO activity values in ΔOD/min/ cm3 of enzyme solution were …
(R)-Β-Lysine Modified Elongation Factor P Functions In Translation Elongation,
2012
The Ohio State University
(R)-Β-Lysine Modified Elongation Factor P Functions In Translation Elongation, Tammy J. Bullwinkle, S. Betty Zou, Andrei Rajkovic, Steven J. Hersch, Sara Elgamal, Nathaniel Robinson, David Smil, Yuri Bolshan, William Wiley Navarre, Michael Ibba
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Post-translational modification of bacterial elongation factor P (EF-P) with (R)-β-lysine at a conserved lysine residue activates the protein in vivo and increases puromycin reactivity of the ribosome in vitro. The additional hydroxylation of EF-P at the same lysine residue by the YfcM protein has also recently been described. The roles of modified and unmodified EF-P during different steps in translation, and how this correlates to its physiological role in the cell, have recently been linked to the synthesis of polyproline stretches in proteins. Polysome analysis indicated that EF-P functions in translation elongation, rather than initiation as proposed previously. This was …
A Comparison Of Boltzmann And Gibbs Definitions Of Microcanonical Entropy For Small Systems,
2012
Brigham Young University
A Comparison Of Boltzmann And Gibbs Definitions Of Microcanonical Entropy For Small Systems, Randall B. Shirts
Faculty Publications
Two different definitions of entropy, S= klnW, in the microcanonical ensemble have been competing for over 100 years. The Boltzmann/Planck definition is that W is the number of states accessible to the system at its energy E (also called the surface entropy). The Gibbs/Hertz definition is that W is the number of states of the system up to the energy E (also called the volume entropy). These two definitions agree for large systems but differ by terms of order N-1 for small systems, where N is the number of particles in the system. For three analytical …
Cloning, Expression, And Characterization Of Ara H 3, A Major Peanut Allergen,
2012
University of New Orleans
Cloning, Expression, And Characterization Of Ara H 3, A Major Peanut Allergen, Cathryn E. Garvey
LSU New Orleans Theses and Dissertations
Abstract There are eight foods that contribute to food allergies in the western world and peanut is the most common. Currently, there are no medical treatments that can cure an individual of food allergy, so avoidance of the allergic food is the only option. In the United States, there are three immunodominant allergic proteins accountable for patient sensitization to peanut, Arachis hypogea 1, 2, and 3 (Ara h 1, Ara h 2, Ara h 3). Therefore, research into why peanuts are more allergic than other foods that have homologous proteins is critical and may be obtained by studying the structural …
Crystal Structures And Kinetics Of Monofunctional Proline
Dehydrogenase Provide Insight Into Substrate Recognition And
Conformational Changes Associated With Flavin Reduction And
Product Release,
2012
University of Missouri-Columbia
Crystal Structures And Kinetics Of Monofunctional Proline Dehydrogenase Provide Insight Into Substrate Recognition And Conformational Changes Associated With Flavin Reduction And Product Release, Min Luo, Benjamin W. Arentson, Dhiraj Srivastava, Donald F. Becker, John J. Tanner
Department of Biochemistry: Faculty Publications
Proline dehydrogenase catalyzes the FAD-dependent oxidation of proline to Δ1- pyrroline-5- carboxylate, which is the first step of proline catabolism. Here, we report the structures of proline dehydrogenase from Deinococcus radiodurans in the oxidized state complexed with the proline analog L-tetrahydrofuroic acid and in the reduced state with the proline site vacant. The analog binds against the si face of the FAD isoalloxazine and is protected from bulk solvent by the α8 helix and the β1-α1 loop. The FAD ribityl chain adopts two conformations in the E-S complex, which is unprecedented for flavoenzymes. One of the conformations is novel for …
Microfluidic Devices With Integrated Sample Preparation For Improved Analysis Of Protein Biomarkers,
2012
Brigham Young University - Provo
Microfluidic Devices With Integrated Sample Preparation For Improved Analysis Of Protein Biomarkers, Pamela Nsang Nge
Theses and Dissertations
Biomarkers present a non-invasive means of detecting cancer because they can be obtained from body fluids. They can also be used for prognosis and assessing response to treatment. To limit interferences it is essential to pretreat biological samples before analysis. Sample preparation methods include extraction of analyte from an unsuitable matrix, purification, concentration or dilution and labeling. The many advantages offered by microfluidics include portability, speed, automation and integration. Because of the difficulties encountered in integrating this step in microfluidic devices most sample preparation methods are often carried out off-chip. In the fabrication of micro-total analysis systems it is important …
Selection Of Trna Charging Quality Control Mechanisms That Increase Mistranslation Of The Genetic Code,
2012
The Ohio State University
Selection Of Trna Charging Quality Control Mechanisms That Increase Mistranslation Of The Genetic Code, Srujana S. Yadavalli, Michael Ibba
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Mistranslation can follow two events during protein synthesis: production of non-cognate amino acid:transfer RNA (tRNA) pairs by aminoacyl-tRNA synthetases (aaRSs) and inaccurate selection of aminoacyl-tRNAs by the ribosome. Many aaRSs actively edit non-cognate amino acids, but editing mechanisms are not evolutionarily conserved, and their physiological significance remains unclear. To address the connection between aaRSs and mistranslation, the evolutionary divergence of tyrosine editing by phenylalanyl-tRNA synthetase (PheRS) was used as a model. Certain PheRSs are naturally error prone, most notably a Mycoplasma example that displayed a low level of specificity consistent with elevated mistranslation of the proteome. Mycoplasma PheRS was found …
Spatial Patterns Of Mercury In Atmospheric Deposition, Soils And Lake Biota In The Adirondack Park, New York,
2012
Syracuse University
Spatial Patterns Of Mercury In Atmospheric Deposition, Soils And Lake Biota In The Adirondack Park, New York, Xue Yu
Civil and Environmental Engineering - Dissertations
Mercury (Hg), as a trace element cycling in the environment, poses a serious health threat to both humans and wildlife due to its toxicity. Atmospheric deposition is the main source of Hg to most remote environments. The Adirondack Park in New York State of the United States receives moderate Hg deposition, and is a region characterized by relatively high concentrations of Hg in the terrestrial and especially aquatic biota. It is important to understand the mechanisms that contribute to the sensitivity of this region to Hg inputs. In my research, studies of the spatial patterns of Hg in atmospheric deposition, …
Secondary Structure, A Missing Component Of Sequence- Based Minimotif Definitions,
2012
University of Nevada, Las Vegas
Secondary Structure, A Missing Component Of Sequence- Based Minimotif Definitions, David P. Sargeant, Michael R. Gryk, Mark W. Maciejewsk, Vishal Thapar, Vamsi Kundeti, Sanguthevar Rajasekaran, Pedro Romero, Keith Dunker, Shun-Cheng Li, Tomonori Kaneko, Martin Schiller
Life Sciences Faculty Research
Minimotifs are short contiguous segments of proteins that have a known biological function. The hundreds of thousands of minimotifs discovered thus far are an important part of the theoretical understanding of the specificity of protein-protein interactions, posttranslational modifications, and signal transduction that occur in cells. However, a longstanding problem is that the different abstractions of the sequence definitions do not accurately capture the specificity, despite decades of effort by many labs. We present evidence that structure is an essential component of minimotif specificity, yet is not used in minimotif definitions. Our analysis of several known minimotifs as case studies, analysis …
Knockout Of The 15 Kda Selenoprotein Protects Against
Chemically-Induced Aberrant Crypt Formation In Mice,
2012
Towson University
Knockout Of The 15 Kda Selenoprotein Protects Against Chemically-Induced Aberrant Crypt Formation In Mice, Petra A. Tsuji, Bradley A. Carlson, Salvador Naranjo-Suarez, Min-Hyuk Yoo, Xue-Ming Xu, Dmitri E. Fomenko, Vadim Gladyshev, Dolph L. Hatfield, Cindy D. Davis
Department of Biochemistry: Faculty Publications
Evidence suggests that selenium has cancer preventive properties that are largely mediated through selenoproteins. Our previous observations demonstrated that targeted down-regulation of the 15 kDa selenoprotein (Sep15) in murine colon cancer cells resulted in the reversal of the cancer phenotype. The present study investigated the effect of Sep15 knockout in mice using a chemically-induced colon cancer model. Homozygous Sep15 knockout mice, and wild type littermate controls were given four weekly subcutaneous injections of azoxymethane (10 mg/kg). Sep15 knockout mice developed significantly (pGBP-1 in humans has been associated with a highly significant, increased five-year survival rate in colorectal cancer patients. In …
Regulation Of The Lipid Raft Localization Of The Gal/Galnac Lectin, An Adhesin On The Surface Of The Human Protozoan Parasite, Entamoeba Histolytica,
2012
Clemson University
Regulation Of The Lipid Raft Localization Of The Gal/Galnac Lectin, An Adhesin On The Surface Of The Human Protozoan Parasite, Entamoeba Histolytica, Amanda Goldston
All Dissertations
Lipid rafts, sterol- and sphingolipid-rich membrane microdomains, have been shown to control virulence in a variety of parasites including Entamoeba histolytica, an intestinal parasite that causes dysentery and liver abscess. Parasite cell surface receptors, such as the Gal/GalNAc lectin, facilitate attachment to host cells and extracellular matrix. The Gal/GalNAc lectin binds to galactose or N-acetylgalactosamine residues on host components, and is composed of heavy (Hgl), intermediate (Igl), and light (Lgl) subunits. Although Igl is constitutively localized to lipid rafts, Hgl and Lgl transiently associate with this compartment in a cholesterol-dependent fashion. Exposure to bonafide Gal/GalNAc lectin ligands is associated with …
