Life Sciences Commons^™

Isolation, Purification, Scanning Electron Microscopy And Bacterial Dna Uptake Of Plant Protoplasts, Bronwyn G. Hughes

Theses and Dissertations

Protoplasts were isolated from tobacco and barley leaves in sucrose or mannitol using commercially available cellulases and macerozymes. Barley growth and protoplast isolation and purification conditions were optimized so that protoplasts were obtained in high yields free of unwanted debris and organelles. A technique for processing barley and tobacco protoplasts for examination by scanning electron microscopy was developed in which protoplasts seem to have maintained their structural integrity. Barley and tobacco protoplasts took up 3H-B. subtilis DNA, 125I-B. subtilis DNA or 125I-M. luteus DNA as a linear function of time (0-6 hr) and DNA concentration (0-200 μg/ml). Up to 16 …

Intermolecular Potential Surfaces From Electron Gas Methods. Ii. Angle And Distance Dependence Of The A’ And A” Ar–No(X^2ii) Interactions, Glen C. Nielson, Gregory A. Parker, Russell T. Pack

Faculty Publications

Angle dependent intermolecular potential energy surfaces for the two states (2A’ and 2A”) that arise from the interaction of ground (X^2II) state NO with Ar are calculated using the electron gas model to obtain the short range interactions. The average and difference of the two interaction energies are fit to analytic forms convenient for use in scattering calculations and joined smoothly onto the long range van der Waals potential previously determined. The results, which appear to be of useful accuracy, and the applicability of the electron gas model to such open shell–closed shell interactions are discussed.

Evidence For Chromium-Insulin Interaction, Ronald Belusko

Dissertations

No abstract provided.

Direct Chemical Evidence For A Supramolecular Protein Structure In The Nuclear Envelope, David Lee Cochran

Theses and Dissertations

Protein subunit structure in the nuclear envelope has not been previously described. Covalent crosslinking of polypeptides provides a method for studying the subunit structure of protein-rich systems. In this study, several polypeptide crosslinking methods have been used to determine associations among polypeptides in isolated chicken erythrocyte nuclear envelope. Interchain associations that exist in the isolated membrane were fixed by crosslinking the polypeptides in the isolated nuclear envelope. Crosslinked and uncrosslinked polypeptides were resolved by electrophoresis in a dissociating detergent system. Each agent caused distinctive alterations in the gel pattern. Certain bands diminished and disappeared while new bands of two or …

Studies On The Mechanism Of Inhibition Of Rna Synthesis By Template Inactivators, Nikos Panayotatos

Dissertations

No abstract provided.

Changes In Morphology And Protein Content Of Neurons And Glia Of The Developing Hamster Cerebral Cortex, Thomas E. Durica

Dissertations

No abstract provided.

Effect Of Altitude On The Peripheral Degradation Of Thyroxine In The Uinta Ground Squirrel (Citellus Armatus), Stuart K. Ware

Theses and Dissertations

Various methods were employed to detect changes in the peripheral degradation of thyroxine (T4) in adult Uinta ground squirrels (Citellus armatus) collected at two different altitudes (5400 and 9000 feet.) Plasma half-life of injected T4-125I (tl/2) was significantly decreased with altitude, as was T4-125I distribution space (TDS) and T4 degradation and secretion rate (TSR). In vitro deiodination of T4-125I by heart homogenates was not affected, while urinary excretion of thyroxine derived iodide was increased at high altitude 44-70 hours post-injection. Both total and free serum T4 concentrations were reduced at high altitude, although not significantly. The cause of the reduced …

A Review Of The Limnology Of And Water Quality Standards For Lake Mead, Charles R. Goldman

Publications (WR)

1. The waters of Las Vegas Bay, a heavily utilized recreational resource, receive discharges from a variety of municipal and industrial waste sources. The U.S. Environmental Protection Agency has determined, on the basis of numerous studies, that the present water quality violates state and federal standards and constitutes a public nuisance. Consultants have advised the Sewage and Wastewater Advisory Committee that rapid abatement of the alleged pollution conditions can be achieved by an advanced wastewater treatment (AWT) plant.

2. The major problems in Las Vegas Bay are an objectionable water color, excessive turbidity, noxious odors, and oxygen depletion in certain …

Report On Wastewater Disposal To Board Of County Commissioners, Clark County Nevada, Clair N. Sawyer

Publications (WR)

This report is concerned with the management of waste-waters and subsurface drainage from the City of Las Vegas and its environs and the BMI complex, all in Clark County, Nevada. The prime objective is to recommend a plan of action which will utilize the natural resources of the area in the least costly manner and still protect Lake Mead for recreational purposes and use as a public water supply, At this writing, conditions in the upper Las Vegas arm of Boulder Basin are quite unsatisfactory for some recreational purposes due to the extensive blooms of algae which develop. Experience at …

A Comparison Of The Rough Sphere Rotational Diffusion Model With Experimental Results For Liquid Methyl Iodide, Dane R. Jones, Scott L. Whittenburg, C. H. Wang

Chemistry and Biochemistry Faculty Publications

No abstract available.

Esr Study Of Free Radicals In Irradiated Single Crystals Of Potassium Hydroxylamine Disulfonate, B. J. Wilson, Robert W. Holmberg

Faculty Publications

Two free radicals formed when single crystals of potassium hydroxylamine disulfonate are irradiated with gamma rays at 77degrees K were studied by ESR. The ESR spectra result from a predominant center (radical A) exhibiting large 14N and 1H hyperfine splittings and from lesser amounts of Fremy's radical [O-dotN(SO3)2-2]. The g and hyperfine tensors of these radicals have been evaluated and are discussed. Radical A, whose identity remains in doubt, may be regarded as the precursor to Fremy's radical; on warming its lines decay and those of Fremy's radical are formed. Lines from radical A decrease in strength and those of …

Final Report - Lake Mead Monitoring Program, James E. Deacon

Publications (WR)

The Lake Mead monitoring program has developed a substantial body of information on the physical, chemical and biological limnology of Lake Mead since 1972. This report summarizes pertinent aspects of that data, with emphasis on studies completed in 1975 -76. It is our continuing hope that the data developed by us will be useful to an ever broader group of users of the water resource represented by Lake Mead. We have been privileged to see our data have a significant influence in some very important water resource decisions over the past four years. There is every reason to expect that …

Studies Of The Purification Of Nad-Dependent And Nadp-Dependent Isocitrate Dehydrogenase By General Ligand Affinity Chromatography, Geoffrey H. Bertkau

Chemistry & Biochemistry Theses & Dissertations

Purification of Yeast NAD⁺-dependent isocitrate dehydrogenase was partially successful when utilizing an NAD⁺-ribosyl-hydrazide Sepharose affinity chromatography column. Although no specific elution system was found, a maximum purification of sixty-five fold was achieved with 0.5M KCl elution. A 38-fold purification was obtained when 20mM NAD⁺ was employed for elution.

Yeast and calf liver NADP⁺-dependent isocitrate dehydrogenase were also found to bind to NAD⁺-ribosyl-hydrazide Sepharose as well as the NAD⁺-dependent enzyme. Again, elution was achieved with either o,5M KCl or 20 mM NADP⁺.

Ammonium sulfate fractionation decreased the yield …

Kinetic And Binding Studies On L-∝-Glycerophosphate Dehydrogenase, Paul Richard Rosevear

Chemistry & Biochemistry Theses & Dissertations

The properties of the coenzyme, NAD, binding site of chicken muscle L-∝-glycerophosphate dehydrogenase were studied. Adenosine monophosphate, adenosine diphosphate and adenosine diphosphoribose were sha.vn to inhibit the enzyme competitively with respect to NAD. The presence of adenosine, pyrophosphate and ribose regions in the coenzyme binding site of the enzyme was suggested by the inhibitor constants obtained for these compounds.

Disodium monoalkyl phosphates, n-butyl to n-dodecyl phosphate, inclusive, were also shown to inhibit the L-∝-glycerophosphate dehydrogenase catalized reaction competitively with respect to NAD. A positive chain length effect was observed in the binding of these compounds to the enzyme, suggesting the …

Distribution Of Stream Pollution In Lake Water, Richard W. Tew, Samuel S. Egdorf, James E. Deacon

Publications (WR)

Wastewater effluent-laden waters from Las Vegas Wash (LVW) form a density current that may be detected in Boulder Basin of Lake Mead at considerable distances from the wash estuary. This led to the suspicion that water from the inflowing stream [40 mgd (1.5 X 10⁵ cu m/day)] might not be rapidly diluted in the enormous volume of the lake [19 mil acre-ft (2.3 X 10¹⁰ cu m)], but might persist as a recognizable entity to the vicinity of the intake of a major water source for populous Clark County, Nev.

Because of the detection sensitivity implicit in the …

Model Studies For Molybdenum Enzymes. The Reduction Of Cytochrome C By Molybdenum(V)-Cysteine Complexes, Glen D. Lawrence

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The reduction of ferricytochrome c ( cyt c^III), as well as some iron ligand complexes and chemically modified derivatives of cyt c^III, by two molybdenum(V)-cysteine complexes has been investigated as a model for electron transfer in molybdenum enzymes. The reduction of cyt c^III by di-μ-oxo-bis [oxo(L-cysteinato)molybdate(V)] (I) is first order in cyt c^III and zero order in I over a wide range in concentration of I at neutral pH. The reduction of cyt c^III by μ-oxo-bisfoxodihydroxo(L-cysteinato) molybdate(V)] (II) is first order in both reactants and has a rate several orders of magnitude greater …

A Batch Method For The Isolation Of Immunogenically Pure Igg, Iga, And Igm From Human Sera, Samuel Christopher Powell

Chemistry & Biochemistry Theses & Dissertations

A method is described for preparing an enriched fraction of the three major antibodies, immunoglobulins IgG, IgA and IgM, from normal human serum by a batch method. Selective precipitation of these proteins was carried out in successive steps using polyethylene glycol (PEG) of average molecular weight 6,000 at concentrations of 7%, 12% and 14% (16) . Zinc sulfate (10 mM) was used to remove highly immunogenic alpha₂ macroglobulin from the IgM fraction. IgA, IgM and IgG were further purified by adsorption methods using DEAE-cellulose. Quantitation and qualitation of the enriched fractions showed nearly complete separation of each of the …

Van Der Waals Interactions Of Carbon Monoxide, Gregory A. Parker, Russell T. Pack

Faculty Publications

Pade approximant methods and experimental frequency dependent polarizabilities are used to calculate reliable van der Waals C6 coefficients for the interaction of CO with He, Ne, Ar, Kr, Xe, H, Li, Na, K, Rb, Cs, H2, N2, O2, CO2, and CO. Error bounds are given for the C6 coefficients and for the CO oscillator strength sums.

Van Der Waals Interactions Of Ii-State Linear Molecules With Atoms. C6 For No(X 2Π) Interactions, Glen C. Nielson, Gregory A. Parker, Russell T. Pack

Faculty Publications

Formulas are derived for the van der Waals Cn coefficients for the interaction of a diatomic molecule in a II electronic state with an S-state atom. Two triatomic states arise from the degenerate IIstate. The average of the two energies has the usual Legendre polynomial (PL) angular dependence, but the difference in energies of the two states is shown to have associated Legendre polynomial (PML with M=2) angular dependence. Procedures for including spin orbit coupling are included, and the extension to interactions of Delta- and Phi-state molecules is discussed. Values of the spherical part of the C6 coefficients for the …

Comment On ''Inelastic Scattering In Atom-Diatomic Molecule Collisions. I. Rotational Transitions In The Sudden Approximation'', Russell T. Pack

Faculty Publications

It is argued that conflicting approximations in a recent paper [J. R. Stallcop, J. Chem. Phys. 61, 5085 (1974)] render the resulting theory invalid.

Enzymes In Heloderma Horridum Venom, S. A. Murphy, Bob D. Johnson, D. H. Sifford

Journal of the Arkansas Academy of Science

A mixture of venom and saliva from the lizard Heloderma horridum was analyzed for esterase, phosphomonoesterase, phosphodiesterase, 5'nucleotidase, and protease activities. Hydrolysis of N-benzoyl-L-arginine ethyl ester occurred at a pH optimum between pH 8.6 and 9.1 with a maximum activity of 452 units per mg per min. Hydrolysis of ptoluenesulfonyl-L-arginine methyl ester occurred at a pH optimum between pH 8.1 and 8.5 with a maximum of only 36 units per mg per min. One mg of the venom mixture liberated 9.3 μM of p nitrophenol from p-nitrophenyl phosphate per minute at an optimum pH between 8.2 and 8.3. Over a …

A Spectrophotofluorometric Analysis Of Serum Vitamin A Levels In A Defined Population, James Ronald Schroeder

Theses and Dissertations

The objectives of this thesis were to examine serum vitamin A levels in two defined populations. The method of analysis was a spectrophotofluorometric technique with a correction formula to account for interfering fluorescence from an identified carotenoid phytofluene (37).

The first population were infants at time of delivery. Infants were divided into two groups depending upon length of gestation. A premature group was identified as having a length of gestation of less than 36 weeks. Term infants were defined as 36 weeks or greater. The mean value of serum vitamin A of eight premature infants was 10.5 μg/100ml (S.E.M.+.78). The …

Influence Of Dietary Fats And Carbohydrates On Lipid Metabolism In Male And Female Rats, Marjorie Ellen Fitch

Journal of the Arkansas Academy of Science

Effects of dietary fats and carbohydrates on lipid metabolism in rats were studied. Male and female 4-week-old rats were divided into 8 groups and fed 4 fat-carbohydrate combinations (beef tallow or safflower oil, each with either sucrose or rice starch). After 4 weeks, animals were killed by exsanguination through the abdominal aorta and livers were removed. Plasma and liver cholesterol and phospholipids were determined qualitatively and quantitatively. Liver moisture, protein, and lipid and the fatty acid composition of the total liver lipid were determined quantitatively. Variations in growth, food efficiency, and lipid metabolism, particularly as manifested by the fatty acid …

Effect Of Estrogen And/Or Supplemental Substrates On Uterine Utilization Of Pyruvate For Lipid Synthesis, Julie W. Harris

Journal of the Arkansas Academy of Science

Precursor incorporation into uterine lipids was examined in vitro after estradiol-17ß administration in immature female rats. The effect of adding supplemental substrates, glucose or gluconate, to the incubation medium on the labeling pattern of pyruvate-3-¹⁴C into uterine lipids was studied. Presence of supplemental substrate in the medium enhanced the incorporation of pyruvate into uterine lipids after two hours of in vivo estrogen treatment. It is suggested that estrogen's acceleration of pyruvate incorporation into lipid may be due to a concomitant effect on glucose metabolism.

Dietary Fat-Carbohydrate Combinations: Their Effects On Lipid Metabolism In Estrogen-Treated Rats, Beverly A. Clevidence

Journal of the Arkansas Academy of Science

Female rats 4 weeks old were fed diets including beef tallow or safflower oil in combination with sucrose or rice starch. At 8 weeks of age, half the rats were orally administered 2 of estrogen (mestranol) in 5 μl of safflower oil and half were fed the vehicle only. After 10 to 14 days of estrogen treatment, rats were fasted and exsanguinated. Alterations were found in weight gain, liver weights, and levels of various lipids in plasma and liver. Most lipid levels were influenced by an interaction of mestranol with one of the dietary factors. No changes were observed in …

The Interaction Of Phenanthridinium Derivatives With Nucleic Acids, Antonis Kindelis

Dissertations

No abstract provided.

Studies Of N⁵, N¹⁰-Methylene Tetrahydrofolate Reductase From Porcine Kidney And Mouse L1210-Induced Tumor Tissues, Purification And Interaction With Antifolates, David W. Jayme

Theses and Dissertations

Methylene tetrahydrofolate reductase has been purified 1000-fold from porcine kidney and 400-fold from mouse L1210-induced tumor tissue by classical methods. The enzyme preparations have been demonstrated to be essentially free of contaminating methionine synthetase and serine transhydroxymethylase activity. Studies of the kinetic properties of the kidney and tumor enzymes, with respect to the reverse reaction using N5-methyl tetrahydrofolate as the variable substrate, have indicated Km values of 2.0 and 2.4 x 10-4 M, respectively. Inhibition of this key branch point enzyme in folate metabolism by a number of antimetabolites indicates that several of these antifolate compounds exhibit enzyme inhibition superior …

Fractionation Of Ribosomal Proteins From Mesophilic And Thermophilic Bacteria, Raymond J. Knaus

Masters Theses

No abstract provided.

The Role Of Zinc In Dihydroorotase, Pamela S. Gilchrist

Dissertations and Theses

Dihydroorotase (4,4—dihydroorotic acid amidolyase, EC 3.5.2.3.) which catalyzes the reversible cyclization of N-carbamyl-L-aspartate to L-dihydroorotate has been purified from orotate-grown Clostridium oroticum. The enzyme is stable in 0.3 M sodium chloride and 10 µ ZnSO₄. Sodium dodecyl sulfate gel electrophoresis indicates the enzyme to be composed of two identical subunits each with a molecular weight of 58,000 + 6000. Dihydroorotase is shown to be a zinc-containing metalloenzyme with 2 g atoms of zinc per 58,000 g of protein. The role of zinc in dihydroorotase is discussed.

The Effect Of Altitude On Thyroid Function Of The Uinta Ground Squirrel (Citellus Armatus), Wendell Lee Wells

Theses and Dissertations

Thyroid uptake and distribution of 125I, concentrations of T4 and T3 in serum and thyroids and concentrations of TSH in serum and pituitaries were measured to determine thyroid function of Uinta Ground Squirrels (Citellus armatus) native to 5,400 and 9,000 feet elevations to evaluate alterations in the state of the thyroid due to increased altitude. Uptake of 125I was 60 percent lower by squirrels from 9,000 feet. Incorporation of 125I into T3 was greater at the higher elevation, but absolute thyroid T3 concentrations were similar at both elevations. No significant differences were found in serum T3 concentrations, but squirrels living …