Biochemistry, Biophysics, and Structural Biology Commons^™

Neutral Sugars In Selected Pit Viper, Elapid, Lizard And Scorpion Venoms, Ahmed El-Sherif, Paul D. Gwinup, Bob D. Johnson, Dewey H. Sifford

Journal of the Arkansas Academy of Science

No abstract provided.

The Relationship Between Whole Brain Catecholamine Depletion In Carassius Auratus And The Exposure To Inescapable Shock In A Learned Helplessness Paradigm, Roderick J. Misunis

Masters Theses

Learned helplessness is a psychological concept that describes the subsequent escape-avoidance behavior of experimental subjects who are exposed to uncontrollable stressors. Subjects after treatment are unable to respond in situations where escape is possible. Two major theorists, Seligman and Weiss, have proposed explanations concerning the phenomena. Seligman feels that the subject is unable to respond due to the fact that the exposure to an uncontrollable stressor has caused him to learn to be "helpless". Weiss feels that the inability to respond can best be described by alterations in the subject's brain neurochemistry, specifically the neurotransmitter norepinephrine. This paper is an …

Reversible Dark-Induced Senescence Of Soybean Root Nodules, N. E. Pfeiffer, Nasir S.A. Malik, Fred W. Wagner

Department of Biochemistry: Faculty Publications

Nodule senescence was induced in intact soybean Glycine max. (L.) Merr., cv Woodworth plants by an 8-day dark treatment. Dark-induced senescence resulted in the complete loss of acetylene reduction activity, a 67% loss of total soluble protein, and an almost complete loss in total leghemoglobin of nodule extracts. Isoelectric focusing gels demonstrated a preferential loss of certain proteins, which was correlated with an increase in endoprotease specific activity toward azocasein. Nodules were completely green after the 8-day dark treatment. If plants were returned to a normal photoperiod after 8 days in the dark, nodules recovered from the dark treatment in …

Proteolytic Activity In Soybean Root Nodules: Activity In Host Cell Cytosol And Bacteroids Throughout Physiological Development And Senescence, Nancy E. Pfeiffer, Cecilia M. Torres, Fred W. Wagner

Department of Biochemistry: Faculty Publications

Root nodules were harvested from chamber-grown soybean (Glycine max L. Merril cv Woodworth) plants throughout development. Apparent nitrogenase activity (acetylene reduction) peaked before seeds began to develop, but a significant amount of activity remained as the seeds matured. Nodule senescence was defined as the period in which residual nitrogenase activity was lost. During this time, soluble protein and leghemoglobin levels in the host cell cytosol decreased, and proteolytic activity against azocasein increased. Degradative changes were not detected in bacteroids during nodule senescence. Total soluble bacteroid protein per gram of nodule remained constant, and an increase in proteolytic activity in …

Historical Patterns Of Phytoplankton Productivity In Lake Mead, Richard T. Prentki, Larry J. Paulson

Publications (WR)

Lake Mead was impounded in 1935 by the construction of Hoover Dam. The Colorado River was unregulated prior to then and therefore was subjected to extreme variations in flows and suspended sediment loads. Hoover Dam stabilized flows and reduced suspended sediment loads downstream, but Lake Mead still received silt-laden inflows from the upper Colorado River Basin. The Colorado River contributed 97% of the suspended sediment inputs to Lake Mead, and up to 140 x 1O⁶ metric tons (t) entered the reservoir in years of high runoff. Most of the sediments were deposited in the river channel and formed an …

Analysis Of The Surface Polysaccharides Of R. Trifolii Su843 And Its Sym Plasmid Alterated Mutants, Jauh-Lin Duh

Masters Theses

The Rhizobium trifolii polysaccharides from SU843 and mutants--HC843(pBR1AN), HC843, 8002--in which the sym plasmid is replaced, absent, or mutated by transposon Tn5 were isolated. The surface polysaccharides of genetically altered mutants were compared quantitatively and qualitatively with one another and with the parent strain. The interpretation of these results is discussed in relation to the function of Rhizobium surface polysaccharides in the symbiotic process. The symbiotic ability of SU843 and mutant strains is as follows: (a) SU843, nod⁺, fix⁺; (b) mutant 8002, roa⁺ (still attaches to root hair), hac^-, nod^-; (c) …

Effects Of Wastewater Discharges On Periphyton Growth In Lake Mead, Nevada-Arizona, Marsha Korb Morris

Publications (WR)

A study of the effects of secondary-treated wastewater on periphyton growth in Lake Mead, Nevada-Arizona was conducted from September 1979 to December 1980. Periphyton ash-free dry weight, chlorophyll-a, dominant species composition, and alkaline phosphatase activity were measured on fiberglass substrates. Substrates were incubated for two to four weeks in littoral and limnetic habitats. Physical and chemical variables and phytoplankton chlorophyll-a were measured concurrently.

Transparency increased with increasing distance from the discharge. Secchi depth ranged from 0.75 m at the discharge confluence (station 2) in August, to greater than 20 m at the most distant stations (stations 9 and 10) in …

Spermidine-Condensed Phi X174 Dna Cleavage By Micrococcal Nuclease: Torus Cleavage Model And Evidence For Unidirectional Circumferential Dna Wrapping., Kenneth A. Marx, Thomas C. Reynolds

Dartmouth Scholarship

Spermidine-condensed phi X174 replicative form (RF) II DNA was digested with micrococcal nuclease to yield seven identifiable DNA bands forming an arithmetic fragment-length series. The DNA monomer unit length was found to be 780 +/- 80 base pairs. This result is most consistent with a proposed model for micrococcal nuclease cleavage of a DNA torus organized by the unidirectional, circumferential wrapping of B-geometry DNA. By a topological consideration, the blunt-end-rod-fusion model for torus formation [Eickbush, T. H. & Moudrianakis, E. N. (1978) Cell 13, 295-306] is shown to be inconsistent with our empirical solution results. We propose a continuous, circumferential …

Development Of A Procedure For Analysis Of High Density Lipoprotein Subclasses, Chan Chin

Chemistry & Biochemistry Theses & Dissertations

Human serum high density lipoprotein subclasses, HDL₂ and HDL₃ , were isolated by preparative salt density gradient ultracentrifugation and further analyzed by electrophoresis on a 4 to 15% concentration gradient polyacrylamide gel.

The separation of the major classes of serum lipoproteins was achieved after a single ultracentrifugation for 272,000 g at 15°c in a swinging bucket rotor. High resolution concentration gradient gel electrophoresis was found to be particularly suitable for the separation of lipoproteins. The isolation of HDL by precipitation methods, heparin-manganese and dextran-magnesium have also been evaluated in this study, and were found not to completely separate …

Isomers Of 5.8s Ribosomal Rna, David Smith

Chemistry & Biochemistry Theses & Dissertations

When whole cell RNA was separated by high resolution PAG (i.e., polyacrylamide gel) electrophoresis, 5.8S rRNA migrated as three higher mobility intense bands, and three faint bands of lower mobility. The three intense bands represent conformational isomers which migrated as a single band under denaturing conditions on PAG. The three faint bands represent conformational isomers of a minor form of 5.8S rRNA which is elongated at the 5' terminus of the molecule. This minor form migrates as a single band of lower mobility than the major form when electrophoresed on a denaturing PAG. The minor form was determined to have …

Electroimmunoassay A New Competitive Protein Binding Assay Using Antibody Selective Electrodes, George Raymond Connell

Chemistry & Biochemistry Theses & Dissertations

The purpose of this study was to utilize concept of antibody selective electrodes to develop a new competitive protein binding assay. This is a new concept and potentially important analytical technique because it combines the advantage of RIA (sensitivity and selectivity) with advantages of electrical assays (speed and low cost).

Electroimmunoassay: A New Competitive Protein Binding Assay Using Antibody Selective Electrodes, George Raymond Connell

Chemistry & Biochemistry Theses & Dissertations

The purpose of this study was to utilize the concept of antibody selective electrodes to developed a new competitive protein binding assay. This is a new concept and a potentially important analytical technique because it combines the advantages of RIA (sensitivity and selectivity) with the advantages of electrical assays (speed and low cost). A conjugate of PGE₂ and dibenzo—18- crown-6 (a cation selective ionophore) was synthesized, and incorporated into a plastic membrane. The ionophore conjugate increased the selectivity of a polyvinyl chloride (PVC) membrane to monovalent cations. Transmembrane potential was altered by anti-PGE₂ antisera in a concentration dependent …

Development Of An On-Line Computer System For Enzyme Kinetics Studies, Jacqueline R. Thweatt

Chemistry & Biochemistry Theses & Dissertations

The PDP-11/10 minicomputer was interfaced to the Beckman 25 ultraviolet/visible spectrophotometer and this on-line computer system was applied to enzyme kinetics studies. This interface involved hardware equipment to locate, amplify, and transmit the analog signal to an analog-to-digital converter, and software to acquire and store the digital data. Data processing programs were used to calculate kinetic parameters and statistical information from the acquired data.

The Varian Cary 219 ultraviolet/visible spectrophotometer can be readily interfaced to the Apple II Plus microcomputer by hardware equipment which can be purchased from the manufacturer. Various software may also be purchased for use in enzyme …

Assay, Purification, And Characterization Of A Pantetheine Hydrolyzing Enzyme From Pig Kidney, Carl Thomas Wittwer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A microsomal glycoprotein hydrolyzing pantetheine to pantothenate and cysteamine has been solubilized and purified to homogeneity as determined by sodium dodecylsulfate electrophoresis. Four rapid, independent assays of pantetheine hydrolysis are described and compared along with a method for localizing enzymatic activity on polyacrylamide gels. The enzyme is solubilized on exposure to butanol and purified by heat treatment, (NH4)₂SO₄ fractionation, hydrophobic chromatography, and hydroxyapatite chromatography. The glycoprotein, purified 5600-fold in 22% yield, has a specific activity of 14 μmoles pantothenate produced/min/mg of protein, 35 times that previously reported. The enzyme has a pH optimum of 9.0-9.5 and a …

Ortho Cyclization Reactions Of Catecholamines, Robert Lee Hudkins

Chemistry & Biochemistry Theses & Dissertations

A study was undertaken to examine the potential for ortho cyclization associated with the synthesis of 1,2,3,4,-tetrahydroisoquinolines using the Pictet-Spengler reaction. Specif1cally, the condensation of the biogenic amines, dopamine, norepinephrine and epinephrine were carefully examined in light of current literature and the facility and extent of ortho cyclization in each case. The para isomers of these three biogenic amine condensation products were isolated and characterized, while only the ortho isomer derived from dopamine was found stable and could be isolated, and structurally identified. These studies demonstrate that a second cyclization product does, in fact, form in each instance and that …

High-Temperature Battery Calorimeter, L. D. Hansen, R. H. Hart, D. M. Chen, H. F. Gibbard

Faculty Publications

A battery calorimeter was built for the measurement of thermal energy generation of high-temperature lithium–aluminum/iron sulfide battery cells, which are under development for electric vehicle propulsion and other energy storage applications. The calorimeter was designed with a temperature range of 400˚–500˚C, a detection limit of 1 mW, and an upper limit of heat flow of 50 W. The results of measurements on 200-Ah LiAl/FeS cells were in excellent agreement with the predictions of thermodynamic calculations based on precise measurements of the total cell polarization and the temperature coefficient of the emf. Details of the construction and operation principles of this …

The Voluntary Water Quality Monitoring Program : 1982 Project Report, Barbara Welch, Judy Potvin, Mary Ellen Dennis

Maine Collection

The Voluntary Water Quality Monitoring Program : 1982 Project Report

by Barbara Welch, Judy Potvin & Mary Ellen Dennis

Division of Environmental Evaluation and Lake Studies, Maine Department of Environmental Protection, Augusta, Maine 1982.

Contents: Understanding Maine's Lakes and Ponds / Acknowledgement / Temperature / Dissolved Oxygen / Other Measures of Lake Water Quality / Nutrients / Algae and Chlorophyll a / Transparency / Morphometry / Sampling / Protection / Classification / Answers to Most Frequently Asked Questions / Glossary of Terms / Appendix A : Maximum, Minimum, and Mean Values / Appendix B : Phosphate Content of Common Cleansers …

Nuclear Envelope Proteins: Chemical Characteristics And Molecular Interactions Of The Lamins, David Lee Cochran

Theses and Dissertations

The lamins are a group of proteins in a residual nuclear envelope fraction derived from the nuclear lamina. The absence of specific functional assays for the two predominant species, lamin A and lamin B, has complicated their biochemical characterization. Initial studies reported in this work involved the enzymic cleavage of isolated lamins A and B and another lamina protein with a molecular weight of 61,000-daltons. The results obtained with each of three enzymes indicated strong similarities between the three nuclear envelope proteins.

Further chemical characterization of the lamins has been achieved. Lamins A, B and C have been separated by …

Organic N-Chloramines: Chemistry And Toxicology, Frank E. Scully, Jr., Maxwell A. Bempong

Chemistry & Biochemistry Faculty Publications

The stability of aqueous solutions of organic N-chloramines, suspected of contaminating chlorinated water, has been studied. Two factors influence the decomposition of solutions of N-chloropiperidine and N-chlorodiethylamine: a spontaneous decomposition and photodecomposition. Since solutions of these compounds are relatively long-lived, a need for an analytical method for their identification is discussed. A new method is described which involves reaction of organic N-chloramines with arenesulfinic acid salts. The method gives high yields of stable arenesulfonamides. Several toxicological studies of N-chloropiperidine are described. The compound is mutagenic by Ames assay in Salmonella typhimurium strain TA 100 and does not require metabolic activation …

Electron Microscopic Demonstration Of Neural Connections Using Horseradish Peroxidase: A Comparison Of The Tetramethylbenzidine Procedure With Seven Other Histochemical Methods, Keith A. Carson, M-Marsel Mesulam

Biological Sciences Faculty Publications

Eight methods for the electron microscopic demonstration of horseradish peroxidase (HRP) labeling have been compared in adjacent series of vibratome sections of mouse lumbar spinal cord. The tracer, a HRP-wheat germ agglutinin (WGA) conjugate, was injected into the gastrocnemius muscle complex. Following retrograde axonal transport to the lumbar motor neurons and transganglionic anterograde transport of the tracer to the dorsal horn, the HRP activity was demonstrated in eight series of adjacent sections of lumbar spinal cord using eight methods. These included procedures using tetramethylbenzidine (TMB), benzidine dihydrochloride (BDHC), o-tolidine, paraphenylenediamine-pyrocatechol (PPD-PC), and 4 methods using 3,3'-diaminobenzidine (DAB). All eight methods …

Correlation Between Glutathione Peroxidase Activity And Selenium Concentrations In Both Plasma And Erythrocytes, Agatha Dudzai Munyanyi

Chemistry & Biochemistry Theses & Dissertations

Plasma and erythrocyte glutathione peroxidase activities and selenium concentrations were determined for 38 apparently healthy female subjects. In addition, erythrocyte lead and plasma lead and iron concentrations were determined in each subject.

Effects of age, smoking, vitamin and mineral supplementation, use of caffeinated beverages and oral contraceptives on glutathione peroxidase activity were determined and interelement relationships were investigated using the one tailed t-test and Spearman Rank Correlation Coefficients

In Vitro Enzymatic Assay Of Rna Methylation, Pamela Jean Eubanks Gallup

Chemistry & Biochemistry Theses & Dissertations

An assay procedure for in vitro enzymatic methylation of mannnalian ribosomal RNA has been developed in this study. The assay procedure, utilized for the comparison of normal and neoplastic methylase activities (using mouse liver and Ehrlich ascites cells as sources of enzyme), is a modification of previously published methods (52,53). A 100,000 x g supernatant (SlOO) enzyme preparation was incubated with 28S-5.8S rRNA and tritium-labeled S-adenosyl-L-methionine. The RNA was extracted, applied to DEAE cellulose paper, washed, and the radioactivity counted. The neoplastic cell methylase preparation was more active in methylating both exogenous neoplastic and normal 28S-5.8S rRNA than the normal …

The Mechanism Of Aerotaxis In Salmonella Typhimurium, Daniel John Laszlo

Loma Linda University Electronic Theses, Dissertations & Projects

Chemotaxis is the migrational response of bacteria to chemical gradients. Aerotaxis, the response to oxygen, was among the earliest observed tactic phenomena, but progress in the study of aerotaxis was previously limited by the available assays. These assays relied upon oxygen depletion by the bacteria to generate the oxygen gradient which elicits the behavioral response. Such assays are unsuitable for analyzing the role of the electron transport system in aerotaxis. In this study the biochemical mechanism of aerotaxis and its relationship to other chemotaxis pathways in Salmonella typhimurium was explored with the aid of two new assays which imposed an …

Chemical And Biological Structure Of Lake Mead Sediments, Richard T. Prentki, Larry J. Paulson, John R. Baker

Publications (WR)

Lake Mead has undergone a serious decline since Glen Canyon Dam was constructed 450 km upstream in 1963.

State fisheries management agencies are concerned that the decline was caused by water level fluctuations and more severe drawdowns during the bass spawning season, when the operation of Hoover Dam was altered during the post-Lake Powell period.

The construction of Glen Canyon Dam and formation of Lake Powell in 1963 drastically altered the natural discharge and temperature cycles and decreased suspended sediment and nutrient loading in the Colorado River inflow to Lake Mead. Recent studies indicate that these changes in nutrient loading …

An Enzyme-Linked Immunosorbent Assay (Elisa) For Pantothenate, Allen H. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An enzyme-linked immunosorbent assay (ELISA) for pantothenate has been developed. Antibodies induced in rabbits against bovine serum albumin-pantothenate conjugate were specifically purified by affinity chromatography. This process served to reduce the amount of endogenous pantothenate attached to the antibody, as well as to purify the antibody. The purified antibodies were covalently linked to alkaline phosphatase (Sigma type VII) with glutaraldehyde (0.05% aqueous solution). An immobilized pantothenate substrate was first obtained by attaching human serum albumin-pantothenate conjugate to the surface of polystyrene culture tubes by passive adsorption. The binding of the enzyme labelled antibody (E-AB) to this substrate is proportionately inhibited …

High Performance Liquid Chromatographic Analysis Of Biogenic Amines, Thais Edwina Ahrendt Keegan

Chemistry & Biochemistry Theses & Dissertations

The objectives of this research were to develop a sensitive method for separation and quantitation of biogenic amines and to apply that procedure by monitoring neurochemical changes resulting from stimuli to the test system.

Primary aromatic amines were derivatized with o-phthalaldehyde-mercaptoethanol prior to chromatography, Separation of the fluorescent adduct was achieved using a μBondapak/ phenyl reversed-phase column and a two-step gradient of methanol:0.08 M acetic acid, pH J.O. Fluorescence was monitored using a J40 nm excitation energy and an emission filter which transmits radiation greater than 400 nm (50% T at 418 nanometers).

Following optimization of the chromatographic conditions, studies …

The Synthesis And Evaluation Of The Biological Activity Of Heterocyclic Analogs Of Phencyclidine, Julian Dew Mckenney Jr.

Chemistry & Biochemistry Theses & Dissertations

Using the classical synthetic approach described by Maddox and co-workers⁴³, the decyanation reaction of 1- piperidinocyclohexane carbonitrile (PCC), 5, was attempted using the heterocyclic anions of 2-methyl-5-nitropyridine, 22, 2-amino-5-nitropyridine, 23, and 2-hydroxy-5-nitropyridine, 24; however, the desired pyridine analogs of phencyclidine (PCP), 1, could not be prepared under these conditions. Attempts to prepare the same analogs via addition of these anions to the iminium tosylate and hydrobromide salts also proved unsuccessful.

The failure to observe the desired decyanation reaction has been attributed to the special sterochemical restrictions of the hindered nitrile of PCC in that facile …

Peptidohydrolases Of Soybean Root Nodules, Nasir S. A. Malik, N. E. Pfeiffer, D. R. Williams, Fred W. Wagner

Department of Biochemistry: Faculty Publications

Nodule extracts prepared from Glycine max var Woodworth possessed endopeptidase, aminoptidase, and carboxypeptidase actiities. Three distinct endopeptidase activities could be resolved by disc-gel electrophoresis at pH 8.8. According to their order of increasing electrophoretic mobility, the first of these enzymes hydrolyzed azocasein and n-benzoyl-LLeu-β-naphthylamide, while the second hydrolyzed n-benzoyl-L-Arg-/8- naphthylamine (Bz-L-Arg-/βNA), n-benzoyl-L-Arg-β-nitroanilide (Bz-L-Arg-βNA), and azocasein. The third endopeptidase hydrolyzed Bz-L-Arg-βNA, Bz-L-Arg-βNA, and hemoglobin. Fractions of these enzymes extracted from electrophoresis gels were shown to have pH optima from 7.5 to 9.8. AU of the endopeptidases were completely inhibited by diisopropylphosphorofluoridate, demonstrating that they were serine proteases.

Methods For Biological, Chemical, And Physical Analyses In Reservoirs, Penelope E. Kellar, Sherell A. Paulson, Larry J. Paulson

Publications (WR)

This manual contains detailed descriptions of biological, chemical and physical sampling and analytical procedures used at the Lake Mead Limnological Research Center. The manual was prepared in response to requests made by numerous individuals involved in the Las Vegas Valley Water Quality Program. This manual represents what we consider to be a reasonably complete compilation of methods useful in studying both general and specific limnological questions. While each section is sufficiently detailed to be of use to investigators with little experience in limnological methodology, the methods can be used on a wide variety of lakes and reservoirs, with relatively little …

The Synthesis And Biochemical Evaluation Of Potential Acetylcholinesterase Reactivators, Andrea Mcdearmid Lunsford

Chemistry & Biochemistry Theses & Dissertations

Objectives of this research were to (1) synthesize, and (2) evaluate new compounds which would be potential reactivators of organophosphate-inhibited acetylcholinesterase.

A series of 1,8-diazafluorenone and 2,2'bipyridylketone oximes and oxime methiodides were synthesized (11, 13, 14, 22, 24). These compounds were developed as structural analogs of 2-PAM (2-Pyridinealdoxime methiodide) and TMB-4 (1,1Trimethylene-Bis(4-formylpyridinium bromide)dioxime), the current drugs of choice for treatment of organophosphorous poisoning.

Acetylcholinesterase from electric eel was inhibited with DFP (diisopropylfluorophosphate), an irreversible-type inhibitor, and the inhibited enzyme was treated with the various reactivator compounds. The reactivation assays were monitored with pH stat apparatus, and the data were evaluated …