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Full-Text Articles in Life Sciences
Investigation Of Fluorescence In Selected Mammals Of Arkansas, C. Renn Tumlison, Terry L. Tumlison
Investigation Of Fluorescence In Selected Mammals Of Arkansas, C. Renn Tumlison, Terry L. Tumlison
Journal of the Arkansas Academy of Science
The adaptive value of fluorescence among the vertebrates has been studied most in fishes and birds, and only a few observations have been published regarding fluorescence in the pelage of mammals. Recently, reports of fluorescence in some marsupials, the platypus, and in flying squirrels have become available. We report the occurrence of fluorescent properties in some mammals from Arkansas. Most carnivores, bats, and rodents did not exhibit the property when viewed under UV light. However, opossums, rabbits, a weasel, muskrats, and moles showed substantial UV response, and a few other mammals showed minor fluorescence. Colors fluoresced included pink, green, and …
Proteomics Of Carbon Fixation Energy Sources In Halothiobacillus Neapolitanus, Jonathan Hunter, Maria Marasco, Ilerioluwa Sowande, Newton P. Hilliard Jr.
Proteomics Of Carbon Fixation Energy Sources In Halothiobacillus Neapolitanus, Jonathan Hunter, Maria Marasco, Ilerioluwa Sowande, Newton P. Hilliard Jr.
Journal of the Arkansas Academy of Science
Through the use of proteomics, it was uncovered that the autotrophic, aerobic purple sulfur bacterium Halothiobacillus neapolitanus displays changes in cellular levels of portions of its carbon dioxide uptake and fixation mechanisms upon switch from bicarbonate to CO2(g) as carbon source. This includes an increase in level of a heterodimeric bicarbonate transporter along with a potential switch between form I and form II of RubisCO. Additional changes are seen in several sulfur oxidation pathways, which may indicate a link between sulfur oxidation pathways as an energy source and carbon uptake/fixation mechanisms.
Synthesis, Characterization, And Properties Of Mononuclear And Dinuclear Ruthenium(Ii) Complexes Containing Phenanthroline And Chlorophenanthroline, Anwar A. Bhuiyan, X. Du
Synthesis, Characterization, And Properties Of Mononuclear And Dinuclear Ruthenium(Ii) Complexes Containing Phenanthroline And Chlorophenanthroline, Anwar A. Bhuiyan, X. Du
Journal of the Arkansas Academy of Science
The study of photophysical and photochemical properties of ruthenium complexes is of great interest for fundamental practical reasons. Ruthenium complexes have been investigated for use in artificial photosynthesis. This paper deals with the synthesis and spectroscopic investigation of custom-designed ruthenium complexes containing phenanthroline and chloro-phenanthroline ligands. These complexes maybe useful for biological electron-transfer studies. The heteroleptic ruthenium monomer complex Ru(phen)2(Cl-phen) (where phen = 1,10-phenanthroline and Cl-phen=5-chloro-1,10-phenanthroline) was prepared in a two-step procedure previously developed in our laboratory. This monomer complex was used to prepare the ruthenium homometallic dimer complex, (phen)2Ru(phen-phen)Ru(phen)2, by utilizing the Ni-catalyzed coupling reaction. Both complexes were purified …
Valence-Length Correlations For Chemical Bonds From Atomic Orbital Exponents, F. D. Hardcastle
Valence-Length Correlations For Chemical Bonds From Atomic Orbital Exponents, F. D. Hardcastle
Journal of the Arkansas Academy of Science
Pauling’s empirical bond valence-length correlation has proven valuable because it offers a quick and convenient way of checking and evaluating molecular structures and determining oxidation states from measured bond lengths. In this study, a simplified quantum-mechanical approach was used to derive Pauling’s empirical bond valence-length relationship by considering overlap of hydrogen-like orbitals. An expression for the b “empirical” fitting parameter was derived in terms of atomic-orbital exponents. A new set of orbital exponents is presented using published atomic/covalent radii and a continuous function for the effective principal quantum. The b parameters calculated from the orbital exponents are consistent with bond …
Theoretical Justification For Bond Valence -- Bond Length Empirical Correlations, F. D. Hardcastle, S. Laffoon
Theoretical Justification For Bond Valence -- Bond Length Empirical Correlations, F. D. Hardcastle, S. Laffoon
Journal of the Arkansas Academy of Science
Bond valence – bond length empirical correlations are of great interest in chemistry, biology, geology and materials science because they offer a quick and convenient way of checking and evaluating molecular structures. Linus Pauling’s relationship is the most commonly used, but is a two-parameter fit where R0 and b must be optimized. In this study, a simplified quantum-mechanical approach was used to derive Pauling’s empirical bond valence – bond length relationship. A covalency factor was also introduced to account for the difference in “softness” between cation and anion (resulting in increased orbital overlap). An expression for the b parameter was …
Mapping Of Ssdna Nicks Within Dsdna Genomes By Two-Dimensional Gel Electrophoresis, Wayne P. Wahls, K. Mark Dewall, Mari K. Davidson
Mapping Of Ssdna Nicks Within Dsdna Genomes By Two-Dimensional Gel Electrophoresis, Wayne P. Wahls, K. Mark Dewall, Mari K. Davidson
Journal of the Arkansas Academy of Science
DNA molecules within chromosomes undergo constant, dynamic changes yet maintain the integrity of the primary DNA sequence. DNA replication, adjustment of helical density, resolution of catenenes, repair of DNA damage, and homologous recombination each involve breakage and religation of the phosphate backbone of the double helix. Although the analysis of dsDNA breaks is facile, the analysis of ssDNA nicks is not. The principal impediment is that conventional, one-dimensional electrophoresis methods cannot readily detect ssDNA nicks in the context of dsDNA breaks. We therefore developed a two dimensional (native/denaturing) gel electrophoresis approach to map the positions of ssDNA nicks. Analysis of …
Rec12 (Spo11) Recominase Of Fission Yeast Promotes A Backup, Distributive Pathway For Chromosome Segregation In Meiosis I, Wallace D. Sharif, Mari K. Davidson, Wayne P. Wahls
Rec12 (Spo11) Recominase Of Fission Yeast Promotes A Backup, Distributive Pathway For Chromosome Segregation In Meiosis I, Wallace D. Sharif, Mari K. Davidson, Wayne P. Wahls
Journal of the Arkansas Academy of Science
We studied the relationship between recombination and segregation in the fission yeast Schizosaccharomyces pombe. In meiosis, chromosomes undergo two rounds of segregation to produce haploid meiotic products. Crossover meiotic ecombination (chiasmata) promotes chromosome segregation during meiosis I; achiasmatic chromosomes often suffer on disjunction in meiosis I. Recl2 protein is a topoisomerase IIortholog that introduces double-strand DNA breaks that nitiate recombination. The red2 null (deletion) and active site (Y98F) mutants lack recombination and crossovers, and onsequently suffer meiosis I nondisjunction. However, null mutants chromosomes segregate to opposite poles more frequently than predicted. Thus, fission yeast has a backup, "distributive segregation" pathway …
Molecular Orbital Studies Of Nitrosyl Metalloporphyrin Complexes, John P. Graham, Genevive Brown
Molecular Orbital Studies Of Nitrosyl Metalloporphyrin Complexes, John P. Graham, Genevive Brown
Journal of the Arkansas Academy of Science
Molecular orbital calculations are applied to the study of the structure and bonding of nitrosyl metalloporphyrin complexes. The Fenske-Hall approximate molecular orbital method and the Amsterdam Density Functional (ADF) method are used. The calculations provide qualitative and quantitative explanations for the observed structural differences between the nitrosyl porphyrin complexes ofiron, manganese, and cobalt. It is proposed that the energy of the highest occupied molecular orbital (HOMO) of these complexes is primarily responsible for the observed structural differences. The interaction between the nitrosyl ligand and metal dz2 orbital results in an antibonding orbital that is occupied in the complexes of Fe …
Analysis Of Phytoestrogens By High Performance Liquid Chromatography, Anne A. Grippo, Yan Xie, Benjamin L. Rougeau, William V. Wyatt
Analysis Of Phytoestrogens By High Performance Liquid Chromatography, Anne A. Grippo, Yan Xie, Benjamin L. Rougeau, William V. Wyatt
Journal of the Arkansas Academy of Science
Phytoestrogens are biochemicals synthesized in plants which mimic steroidal estrogen activity in mammals. Analysis of these compounds in the legumes which produce them and in body fluids is important to the study of their physiological effects. High pressure liquid chromatography (HPLC) has been found to be an efficient and sensitive method of identification and quantitation of isoflavonoids, one class of phytoestrogen. Here we report the separation of three isoflavonoids, biochanin A, genistein and daidzein using an HPLC system with a Cg reverse phase column and a linear gradient mobile phase containing acetonitrile and acetic acid/water (10/90, v/v) over 60 minutes. …
Electron Shock Waves, Frances Terry, Mostafa Hemmati
Electron Shock Waves, Frances Terry, Mostafa Hemmati
Journal of the Arkansas Academy of Science
No abstract provided.
Application Of A Modified Ziehl-Neelsen's Carbol-Fuchsin Stain For Observing Nuclei In Vegetative Hyphae Of The Puffball Species Lycoperdon Pyriforme, Martin J. Huss
Journal of the Arkansas Academy of Science
Nuclei of vegetative hyphae of the puffball species Lycoperdon pyriforme are small and difficult to stain. A simple mitotic staining technique utilizing a modified version of Ziehl-Neelsen's carbol-fuchsin stain, originally developed for examining bacteria and small chromosomes of plants, has proven useful for observing fungal nuclei in this gasteromycete species. Cells of vegetative hyphae were pre-treated for 2 hours with an aqueous solution saturated with naphthalene, fixed in a 3:1 mixture of 100% ethanol and glacial acetic acid, and hydrolyzed for 10 minutes in a 1:1 mixture of 100% ethanol and 12 M hydrochloric acid. Cells were rinsed with distilled …
Thermal Decomposition Studies Of Selected Transition Metal Polysulfide Complexes. Ii. Effect Of Atmosphere On Decomposition, Benjamin Rougeau, Mark Draganjac
Thermal Decomposition Studies Of Selected Transition Metal Polysulfide Complexes. Ii. Effect Of Atmosphere On Decomposition, Benjamin Rougeau, Mark Draganjac
Journal of the Arkansas Academy of Science
Initial studies involved the thermal decomposition profile of five polysulfide complexes in air up to 550 °C. Since our first report to the Academy in 1990, we have obtained the capability to run samples up to 1500°C under various gases. Thermal Gravimetric Analysis (TGA) and Differential Thermal Analysis (DTA)of a series of transition metal polysulfide complexes are presented. Compounds analyzed included Cp2TiS5 ,MoS9 2",MoOS8 2", Zn(S x ) 2", Cd(S x ) 2-, Fe2S122 - and NiS82.
Multisite Microprobes For Electrochemical Recordings In Biological Dynamics, G. Sreenivas, S. S. Ang, R. M. Ranade, A. S. Salian, W. D. Brown
Multisite Microprobes For Electrochemical Recordings In Biological Dynamics, G. Sreenivas, S. S. Ang, R. M. Ranade, A. S. Salian, W. D. Brown
Journal of the Arkansas Academy of Science
For over 30 years, techniques have been developed that allow for the microscale (10-30 /mum) measurement of chemical signals with high temporal resolution (1-200 Hz). Such measurements, called in vivo electrochemical recordings, allow for the direct determination of neurotransmitter molecules and related compounds in biological systems. Multiple recordings, simultaneously performed at different, closely spaced, well defined locations throughout a three-dimensional tissue volume in the brain, are of interest in neuroscience. Developments in microelectronic techniques enable the fabrication of multi-electrode microprobes for recording extracellular action potentials generated by individual neurons simultaneously. A high-yield microfabrication process has been successfully developed for the …
Effective, Reliable, Inexpensive Cryofixation Device, Lawrence A. Mink, Roger A. Buchanan
Effective, Reliable, Inexpensive Cryofixation Device, Lawrence A. Mink, Roger A. Buchanan
Journal of the Arkansas Academy of Science
No abstract provided.
Rotational Symmetries Of Nuclear States: Spin Determinations In Advanced Laboratory, Wilfred J. Braithwaite
Rotational Symmetries Of Nuclear States: Spin Determinations In Advanced Laboratory, Wilfred J. Braithwaite
Journal of the Arkansas Academy of Science
An advanced laboratory experiment is described which shows the connection between the rotational symmetries of nuclear states and the assignments of spins to discrete nuclear states. Standard angular correlation methods were used to study the two sequential gamma ray transitions in each ⁶⁰Ni nucleus, populated by unobserved beta decays from a weak radioactive ⁶⁰Co source. The chosen electronics and detectors were inexpensive and easy to operate. This experiment was extended to introduce students to real-world data acquisition, using finite-geometry detectors, which resulted in enormously larger coincident data rates.
Mermithid Nematodes: Sem Observations Comparing Hexamethyldisilazane And Critical Point Drying Methods, William R. Bowen, Christopher C. Hemann, Arthur A. Johnson, Barry H. Good
Mermithid Nematodes: Sem Observations Comparing Hexamethyldisilazane And Critical Point Drying Methods, William R. Bowen, Christopher C. Hemann, Arthur A. Johnson, Barry H. Good
Journal of the Arkansas Academy of Science
Morphological features of mermithid nematodes (Mermithidae) were studied with scanning electron microscopy, using hexamethyldisilazane-air drying in comparison with critical point drying via liquid carbon dioxide. Although general morphologic preservation of both HMDS-dried and CP-dried specimens was similar, structural features of the complex cuticle and internal organization were more easily resolved at higher magnifications in the HMDS-dried nematodes. These features include the superficial cuticular annulations, the fibrillar inner cuticle and peg-like microtrabeculae. The previously undescribed microtrabeculae are of special interest since they may facilitate an interaction of the mermithid (and perhaps nameatodes in general) musculature with its body wall that, at …
Conformational And Circular Dichroism Studies On N-Acetyl-L-Prolyl-D-Alanyl-Methylamide, S. Ramaprasad
Conformational And Circular Dichroism Studies On N-Acetyl-L-Prolyl-D-Alanyl-Methylamide, S. Ramaprasad
Journal of the Arkansas Academy of Science
The compact ordered conformations of the molecule N-Acteyl-L-Prolyl-D-Alanyl-Methylamide have been studied by semiempirical energy calculations in vacuum and circular dichroism (CD) in solution. The presence of ordered structure has been observed in hydrogen bond promoting solvents like trifluoroethanol by CD studies. In hydrogen bond breaking solvents, like trifluoroacetic acid (TFA), significant fraction of the ordered conformers probably assume extended conformation without intramolecular hydrogen bonds and perhaps are in equilibrium with the fraction of compact ordered structures. The trend observed in going from nonpolar to polar solvent is also compatible with the previous NMR studies in solution. The semiempirical energy calculations …
Comparison Of Cyclic Nucloetide Phosphodiesterase In Physarum Favicomum, C. Kay Holtman, Tammy K. Ebsen, Judith A. Bean, J. Scott Bryles, Thomas J. Lynch
Comparison Of Cyclic Nucloetide Phosphodiesterase In Physarum Favicomum, C. Kay Holtman, Tammy K. Ebsen, Judith A. Bean, J. Scott Bryles, Thomas J. Lynch
Journal of the Arkansas Academy of Science
We have studied both cyclic AMP phosphodiesterase and cyclic GMP phosphodiesterase in the myxomycete Physarum flavicomum. The cyclic AMP phosphodiesterase preparations were isolated from both the diploid plasmodial stage of the lifecycle and the haploid myxamoebal stage. The plasmodial enzyme was prepared from spent medium (extracellular) and also from purified nuclei. The myxamoebal enzyme was prepared from purified nuclei. Cyclic GMP phosphodiesterase activity was studied in purified nuclei isolated from the plasmodium. One unusual feature of all the enzymes from the plasmodium is extreme heat stability; they remain catalytically active even after exposure to a boiling water bath for twenty …
Photoreactivation Of Lethal Damage Induced In Hamster X Xenopus Hybrid Cells And Their Parentals By Uv Light, David Bohlender, Stuart Williams, Emir Cruz, H. Gaston Griggs
Photoreactivation Of Lethal Damage Induced In Hamster X Xenopus Hybrid Cells And Their Parentals By Uv Light, David Bohlender, Stuart Williams, Emir Cruz, H. Gaston Griggs
Journal of the Arkansas Academy of Science
A85 Xenopus cells that exhibited a high level of photoreactivation (PR) and V79B2 hamster cells that exhibited little PR were fused to produce the V79B2 x A85 cell line — a hybrid line which possessed a relatively stable karyotype, with most cells containing the entire V79B2 and A85 genomes. UV and UV plus PR fluence-survival relations were then determined and compared for the hybrid and parental lines in a first attempt to elucidate interactions of the parental PR mechanisms in the hybrid. It was anticipated that the A85 genome in the hybrid would produce PR enzyme in sufficient concentration and …
Spectrophotomatic Assay For The Enzyme Catalyzed Reaction Of 4-Nitroquinoline 1-Oxide With Glutathione, J. Steven Stanley, Ann M. Benson
Spectrophotomatic Assay For The Enzyme Catalyzed Reaction Of 4-Nitroquinoline 1-Oxide With Glutathione, J. Steven Stanley, Ann M. Benson
Journal of the Arkansas Academy of Science
4-Nitroquinoline 1-oxide (4NQO(is a toxic and carcinogenic compound that has been reported to be subject to conjugation with glutathione (GSH). This reaction may proceed non-enzymatically or be catalyzed by GSH transferases. The non-enzymatic rate for this reaction has been reported to be very high. The purposes of this investigation were to develop a spectrophotometric assay for the reaction of4NQO with GSH and to determine whether the rate for the enzyme catalyzed reaction was significant relative to the non-enzymatic reaction. The absorbance spectrum of 4NQO in phosphate buffer exhibited a maximum at 365 nm. Reaction of 4NQO with GSH was accompanied …
Isolation Of Nuclei From Physarum Flavicomum: Demonstration Of Nuclear Cyclic Acid Amp Phosphodiesterase, Judith A. Bean, Maurice G. Kleve, Thomas J. Lynch
Isolation Of Nuclei From Physarum Flavicomum: Demonstration Of Nuclear Cyclic Acid Amp Phosphodiesterase, Judith A. Bean, Maurice G. Kleve, Thomas J. Lynch
Journal of the Arkansas Academy of Science
Cyclic AMP phosphodiesterase activity in the nucleus of the myxomycete Physarum flavicomum was demonstrated by cytochemical staining utilizing electron microscopy and by enzymatic assays with tritiated cyclic AMP as the substrate. Cytochemical staining showed Physarum's plasmodial phosphodiesterase activity to be located in the nucleus, along the plasma membrane, in vesicles, and free in the cytoplasm. Nuclear phosphodiesterase, which may be cell cycle dependent, was primarily located in the nucleolus. Nuclei from three to five day old microplasmodial cultures were isolated by the method of Henney and Yee. Whole cells were collected through centrifugation and washed. Pellets were homogenized in a …
Concanavalin A-Nonbinding Enzymes Of Crotalus Scutulatus Scutulatus Venom, C. K. Childs, Michael W. Hinson, Dewey H. Sifford, Bob D. Johnson
Concanavalin A-Nonbinding Enzymes Of Crotalus Scutulatus Scutulatus Venom, C. K. Childs, Michael W. Hinson, Dewey H. Sifford, Bob D. Johnson
Journal of the Arkansas Academy of Science
Crotalus scutulatus scutulatus crude venom was separated into two fractions by Concanavalin A Sepharose 4B affinity chromatography. The Concanavalin A-nonbinding fraction (F-l) exhibited phosphomonoesterase (orthophosphoric monoester phosphohydrolase EC 3.1 .3.2), phosphodiesterase, 5 '-nucleotidase (5 '-ribonucleotide phosphohydrolase EC 3.1.3.5), phospholipase A (phosphatidate 2-acylhydrolase EC 3.1.1.4), hyaluronidase (hyaluronate glycanohydrolase EC 3.2.1.d), N-benzoyl-Larginine ethyl esterase, p-toluenesulfonyl-L-arginine methyl esterase, L-amino acid oxidase (L-amino acid: O2 oxidoreductase [deaminating] EC 1.4.3.2), and caseinolytic activities. Thrombin-like and NAD nucleosidase (5 '-ribonudeotide phosphohydrolase EC 3.1.3.5) activities were not observed. DEAE Sephadex A-50 ion exchange chromatography by two stage elution of F-l yielded several fractions having proteinase activities. Proteinase …
Optimal Conditions For Kinetic Study Of Succinate Dehydrogenase In Rat Liver, Collie B. Shaw, Tara L. Chronister, John D. Peck
Optimal Conditions For Kinetic Study Of Succinate Dehydrogenase In Rat Liver, Collie B. Shaw, Tara L. Chronister, John D. Peck
Journal of the Arkansas Academy of Science
Succinate dehydrogenase (SDH) commonly is assayed as a marker enzyme for mitochondrial activity. The literature presents numerous conditions for conducting this assay due to the fact that, it has been difficult to get sufficient reduction of the acceptor dye, 2,3,5-triphenyl-2H-tetrazolium chloride (TTC). This study was undertaken to optimize the SDH-catalyzed reduction of TTC dye by evaluation of a greater range of molor ratios of TTC to succinate and by further evaluation of additives reported as beneficial. Improvement in enzyme specific activity was achieved by liver perfusion via the left cardiac ventricle with homogenizing solution. Increase in TTC from 1 to …
Plasma Corticosterone Levels In Cholesterol-Fed Cockerels Before And After A Twenty Minute Run, Stanley N. David, Clarene L. David
Plasma Corticosterone Levels In Cholesterol-Fed Cockerels Before And After A Twenty Minute Run, Stanley N. David, Clarene L. David
Journal of the Arkansas Academy of Science
Cockerels were exercised to observe the influence of physical activity on plasma corticosterone concentrations. The birds were maintained on a commercial mash or on an atherogenic diet. Plasmas were collected on the first day, fifteen days after the first collection and immediately after a 20 minute run on that fifteenth day. The plasma corticosterone levels as determined by radioimmunoassay showed extreme variations within collections. Hence, the data analysis indicated no significant changes of the Compound β in the blood of the cockerels due to diet, or exercise or the combination of both. The causes for the wide variation of plasma …
Effects Of Juglone (5'-Hydroxy-1, 4-Naphthoquinone) On The Algae Anabaena Flos-Aquae, Nostoc Commune, And Scenedesmus Acuminatus, V. Diane Randall, Jimmy D. Bragg
Effects Of Juglone (5'-Hydroxy-1, 4-Naphthoquinone) On The Algae Anabaena Flos-Aquae, Nostoc Commune, And Scenedesmus Acuminatus, V. Diane Randall, Jimmy D. Bragg
Journal of the Arkansas Academy of Science
Three species of algae, Anabaena flos-aquae, Nostoc commune and Scenedesmus acuminatus were selected for their sensitivity to juglone and studied for the effects of juglone concentrations of 10, 1, 0.5, 0.1 and 0.01 μg/ml upon their growth. A. flos-aquae was most sensitive, with significant inhibition by the 0.5 μg/ml concentration. N. commune was inhibited least, with significant inhibition only in the 10 μg/ml concentration. S. acuminatus was found to be moderately inhibited at the 0.5 μg/ml concentration. All species were found to be non-viable after 14 days exposure to 10 μg/ml juglone. Tests with 7 and 14 day old cells …
Effects Of Gamma Radiation On Salix Nigra Marsh Cuttings, Roy Z. Gehring
Effects Of Gamma Radiation On Salix Nigra Marsh Cuttings, Roy Z. Gehring
Journal of the Arkansas Academy of Science
Dormant cuttings of Salix nigra Marsh, were exposed to gamma radiation from a cobalt-60 source at a dose rate of 1110 roentgens (r) per minute. Exposure doses ranged from 50 r through 100 Kr with 100% mortality at 10 Kr. Low doses of ionizing radiation apparently stimulated growth, while higher doses progressively retarded growth. The growth of the staminate catkins was inversely proportional to total exposure dose (increased dose resulted in progressively decreased growth). Determination of growth rates at different intervals post-irradiation indicated recovery of the surviving fraction of the irradiated cuttings. At ninety days, the highest growth rate occurred …
Concanavalin A-Binding Enzymes Of Crotalus Scutulatus Scutulatus Venom, Michael W. Hinson, C. K. Childs, Bob D. Johnson, Dewey H. Sifford
Concanavalin A-Binding Enzymes Of Crotalus Scutulatus Scutulatus Venom, Michael W. Hinson, C. K. Childs, Bob D. Johnson, Dewey H. Sifford
Journal of the Arkansas Academy of Science
Crotalus scutulatus scutulatus crude venom was separated into two fractions by Concanavalin A Sepharose 4B affinity chromatography. The proteins binding to Con A exhibited phosphomonoesterase (orthophosphoric monoester phosphohydrolase EC 3.1.3.2), phosphodiesterase, 5'-nucleotidase (5'-ribonucleotide phosphohydrolase EC 3.1.3.5), phospholipase A(phosphatidate 2-acylhydrolase EC 3.1.1 .4), hyaluronidase (hyaluronate glycanohydrolase EC 3.2.1 d), N-benzoyl-L-arginine ethyl esterase, p-toluenesulfonyl-L-arginine methyl esterase, L-amino acid oxidase (L-amino acid: 02 oxidoreductase [deaminating] EC 1.4.3.2), and caseinolytic activities. Thrombin-like and NAD nucleosidase (5'-ribonucleotide phosphohydrolase EC 3.1.3.5) activities were not observed. The crude venom and the fraction containing the glycoproteins which bound to Con A were fractionated by DEAE Sephadex A-50 ion …
Role Of Centriolar Matrix And Striated Rootlets In Centriolar Pairing And Orientation During Spermatogenesis In Hydractina Echinata, Maurice G. Kleve
Role Of Centriolar Matrix And Striated Rootlets In Centriolar Pairing And Orientation During Spermatogenesis In Hydractina Echinata, Maurice G. Kleve
Journal of the Arkansas Academy of Science
Transmission electron microscopy of the spermatogenic stages of the hydroid, Hydractinia echinata, reveals a series of complex structural and positional changes in the centrioles of spermatocytes and spermatids. The newly generated centriolar pairs of spermatocytes form an unusual four-centriole aggregate that persists until cell division. The distal centrioles of this aggregate are shrouded with a very dense matrix that accumulates after centriolar replication. This matrix facilitates the mechanical attachment between distal centrioles and microtubular nucleating satellites, striated rootlets and pericentriolar processes. The association of these accessory structures occurs sequentially and is repeated in spermatocytes and spermatids. An electron dense plaque, …
Demonstration Of A Heat-Stable Cyclic Gmp Phosphodiesterase In The Medium Of Physarum Flavicomum, Thomas J. Lynch, Mark S. Ross
Demonstration Of A Heat-Stable Cyclic Gmp Phosphodiesterase In The Medium Of Physarum Flavicomum, Thomas J. Lynch, Mark S. Ross
Journal of the Arkansas Academy of Science
No abstract provided.
Effects Of Growth Temperatures On The Fatty Acid Composition Of Isolated Chloroplasts From Two Species Differing In Heat Sensitivity, Roy Z. Gehring, Glenn W. Todd
Effects Of Growth Temperatures On The Fatty Acid Composition Of Isolated Chloroplasts From Two Species Differing In Heat Sensitivity, Roy Z. Gehring, Glenn W. Todd
Journal of the Arkansas Academy of Science
Lipid analyses of chloroplasts isolated from wheat (Triticum aestivum L. cv. Arthur) and milo (Sorghum bicolor cv. Funk's hybrid 522) suggest no major heat effect on lipid class distribution. Assuming milo is more heat tolerant than wheat and that increased saturated/unsaturated fatty acid values increase thermal stability, changes in sulfoquinovosyldiglyceride (SL) appear to be more important than phosphatidylglycerol (PG) in conferring thermal stability to isolated chloroplasts.