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Biochemistry, Biophysics, and Structural Biology

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Articles 13021 - 13050 of 13221

Full-Text Articles in Life Sciences

Grape Guards Prove Their Worth, Department Of Agriculture, Western Australia Jan 1973

Grape Guards Prove Their Worth, Department Of Agriculture, Western Australia

Journal of the Department of Agriculture, Western Australia, Series 4

now being packed and protected with "grape guards"—gas releasing generators consisting of chemically treated paper which releases small quantities of sulphur dioxide. Grape guards inserted in unventilated storage boxes are activated by the high humidity in the box to release their sulphur dioxide and prevent decay of the packaged fruit. The guards were developed in the United States two years ago.


Characterization Of A Fatty Acid Synthetase From Corynebacterium Diphtheriae, Herman W. Knoche, Kirston E. Koths Jan 1973

Characterization Of A Fatty Acid Synthetase From Corynebacterium Diphtheriae, Herman W. Knoche, Kirston E. Koths

Department of Biochemistry: Faculty Publications

A fatty acid synthetase from Corynebacterium diphtheriae has been purified to a specific activity of 450 nmoles of malonyl coenzyme A incorporated per min per mg. The enzyme is optimally active in 0.5 M phosphate buffer. C. diphtheriae appears to be the most primitive organism having a multienzyme complex for fatty acid synthesis.


Palmityl Coenzyme A Inhibition Of Fatty Acid Synthesis, Herman Knoche, Theodore W. Esders, Kirston Koths, Konrad Bloch Jan 1973

Palmityl Coenzyme A Inhibition Of Fatty Acid Synthesis, Herman Knoche, Theodore W. Esders, Kirston Koths, Konrad Bloch

Department of Biochemistry: Faculty Publications

The effects of acyl-CoA derivatives (C8 to C20) on the activity

of the fatty acid synthetases from yeast and Corynebacterium

diphtheriae have been examined. Both enzyme

systems are inhibited by the longer chain acyl thioesters

(C16 to C20) and protected against this inhibition by bovine

serum albumin (BSA). Identical relief from acyl-CoA inhibition

is provided by the 6-0-methylglucose-containing

lipopolysaccharide (MGLP), from Mycobacterium phlei. It

is shown that MGLP forms a stable complex with palmitylCoA.

This interaction accounts for the BSA-like effects of

the polysaccharide. BSA and MGLP have two further effects

on the fatty …


Studies Of The Effects Of Solvent Composition On The Association-Dissociation Of Oxyhemerythrin As Determined By Analytical Gel Chromatography, Kim Hock Tan Jan 1973

Studies Of The Effects Of Solvent Composition On The Association-Dissociation Of Oxyhemerythrin As Determined By Analytical Gel Chromatography, Kim Hock Tan

Dissertations

No abstract provided.


Proboscipedia, A Homeotic Mutant In Aedes Aegypti (L.) (Diptera: Culicidae), John Roach Roberts Jr. Jan 1973

Proboscipedia, A Homeotic Mutant In Aedes Aegypti (L.) (Diptera: Culicidae), John Roach Roberts Jr.

College of Graduate Studies: Theses & Dissertations (1964–2006)

No abstract provided.


Polysomes From Mesophilic And Thermophilic Bacteria, Philip Y. Shen Dec 1972

Polysomes From Mesophilic And Thermophilic Bacteria, Philip Y. Shen

Dissertations

No abstract provided.


On Improved Wkb (Uniform Asymptotic) Quantum Conditions, Dunham Corrections, The Langer Modification, And Rkr Potentials, Russell T. Pack Dec 1972

On Improved Wkb (Uniform Asymptotic) Quantum Conditions, Dunham Corrections, The Langer Modification, And Rkr Potentials, Russell T. Pack

Faculty Publications

An improvement to the WKB quantum condition for the rotation-vibration levels of diatomic molecules, known empirically to give RKR potentials of increased accuracy and to account for the Dunham correction Y00, is derived using uniform asymptotic methods. The role of the Langer transformation in this problem is also discussed.


The Fidelity Of Dna Polymerase From Bacillus Licheniformis And Bacillus Stearothermophilus, Gerald R. Mcgowan Dec 1972

The Fidelity Of Dna Polymerase From Bacillus Licheniformis And Bacillus Stearothermophilus, Gerald R. Mcgowan

Masters Theses

No abstract provided.


Phytoplankton Successions And Lake Dynamics In Las Vegas Bay, Lake Mead, Nevada, Ervon R. Koening, Richard W. Tew, James E. Deacon Oct 1972

Phytoplankton Successions And Lake Dynamics In Las Vegas Bay, Lake Mead, Nevada, Ervon R. Koening, Richard W. Tew, James E. Deacon

Publications (WR)

Phytoplankton successions, applications of the general growth equation, and physical measurements have been employed to investigate events occurring at the interface between industrial and sewage effluent contained in Las Vegas Wash and the waters of Lake Mead, Nevada. The data indicate that the entering waters tend to form a density current interrupted at intervals by dynamic effects generated in the lake. The dynamic relationships described here for the spring months suggest that a much more thorough understanding of physical, chemical and biological interactions is necessary to permit solution of the numerous problems of Las Vegas Bay discussed or alluded to …


A Mathmatical Model Of Primary Productivity And Limnological Patterns In Lake Mead, Lorne G. Everett Sep 1972

A Mathmatical Model Of Primary Productivity And Limnological Patterns In Lake Mead, Lorne G. Everett

Publications (WR)

The temporal and spatial changes in chemical and biological properties of Lake Mead have been investigated, thereby indicating the sources of water pollution and the time of highest pollution potential. Planktonic organisms have been shown to indicate the presence of water problems. Macro- and micro-nutrient analyses have shown that primary productivity is not inhibited by limiting concentrations. A mathematical model has been developed, tested with one set of independent data, and shown worthy of management utility. Although the model works very well for the Lake Mead area, the physical reality of the Multiple Linear Regression equation should be tested on …


Lipids Of Fungal Spores, Identification And Metabolism, Jim L. Bushnell Aug 1972

Lipids Of Fungal Spores, Identification And Metabolism, Jim L. Bushnell

Theses and Dissertations

The lipids of the spores of the Basidiomycetes: Ustilago bullata, Lycoperdon perlatum and Calvatia gigantea were investigated. The spores of U. bullata were found to have hydrocarbons ranging from C_9 to C_24, methyl esters of fatty acids ranging from C_14 to C_24, and free fatty acids from C_14 to C_24. The spores of L. perlatum were found to have few hydrocarbons (C_22 being the predominent one); no methyl esters were detected and the fatty acids were from C_15 to C_18. Long chain aldehydes (C_30) were also detected in low concentration. At the ultrastructural level the Lycoperdon spores were found to …


Immunochemical Studies Of Ribosomes From Mesophilic And Thermophilic Bacteria, Thomas L. Snyder Aug 1972

Immunochemical Studies Of Ribosomes From Mesophilic And Thermophilic Bacteria, Thomas L. Snyder

Masters Theses

No abstract provided.


Enzymatic Synthesis Of Oligoribonucleotides Of Defined Base Sequence, Bronwyn Geraldine Hughes Jul 1972

Enzymatic Synthesis Of Oligoribonucleotides Of Defined Base Sequence, Bronwyn Geraldine Hughes

Theses and Dissertations

A possible method for the synthesis of ordered oligoribonucleotides involves primer-dependent polynucleotide phosphorylase (PNPase) synthesis using the RNase A or T1 resistant N-cyclohexyl-N'-β(4-methylmorpholinium)ethylcarbodiimide chloride (CMC-Cl) derivatives of uridine or guanosine containing primers. Thus, CMC-UpA, CMC-GpA, CMC-UpCpC, CMC-GpApC, and ApApApApU-CMC were prepared and studied as primers for PNPase in 15 min 14C-ADP polymerization reactions and also in 6-10 hr synthesis reactions. The CMC-primers were not suitable primers for PNPase catalyzed synthesis reactions for either time. The PNPases used in such studies were contaminated with nuclease that showed the following order of susceptibility: UpA > CpC, GpA > ApU, ApA. Even a highly purified …


The Comparative Histochemistry Of The Infective Oncospheres Of Oochoristica Osheroffi Meggitt, 1934, And Oochoristica Scelopori Voge And Fox, 1950, (Cyclophyllidea: Linstowiidae) With Notes On The Origins Of The Egg Membranes, Gary R. Coulter Jun 1972

The Comparative Histochemistry Of The Infective Oncospheres Of Oochoristica Osheroffi Meggitt, 1934, And Oochoristica Scelopori Voge And Fox, 1950, (Cyclophyllidea: Linstowiidae) With Notes On The Origins Of The Egg Membranes, Gary R. Coulter

Loma Linda University Electronic Theses, Dissertations & Projects

Infective oncospheres of Oochorlstica osheroffi and Oochoristica scelopori were compared using fifteen histochemical tests. Vital stains were also used.

Carnoy’s-fixed gravid proglottids were vacuum-embedded in a paraffin-piccolyte mixture and cut transversely at 6 microns. Sections were tested for the presence of phosphatases, proteins, sclerotin precursors, nucleic acids, carbohydrates and acid mucopolysaccharides.

Oncospheres were histochemlcally very similar. Heavy concentrations of mucoproteins and glycoproteins were detected in the oncospheral coat of O. scelopori. Acid phosphatase was found in the embryophore of O. osheroffi, but could not be demonstrated in O. scelopori. No evidence of a sclerotized egg capsule was …


Model For Estimating Soil Water Flow, Water Content, Evapotranspiration And Root Extraction, Musa N. Nimah May 1972

Model For Estimating Soil Water Flow, Water Content, Evapotranspiration And Root Extraction, Musa N. Nimah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A mathematical model was developed to predict water content profiles, evapotranspiration, water flow from or to the water table, root extraction and root water potential at the surface as functions of time under unsteady state conditions.

The model was tested in the field at The Hullinger Farm near Vernal, Utah, in 1970 and 1971. Comparison of water content-depth profiles show excellent agreement at the end of a 9- day run in 1970 on oats seeded to alfalfa. In 1971 with alfalfa as the crop, the data show best agreement, between predicted and computed water content-depth profiles, 48 hours after any …


Purification And Properties Of Phenylalanine Transfer Rna From Bacillus Licheniformis And Bacillus Stearothermophilus, Cynthia R.Y. Yang Apr 1972

Purification And Properties Of Phenylalanine Transfer Rna From Bacillus Licheniformis And Bacillus Stearothermophilus, Cynthia R.Y. Yang

Dissertations

No abstract provided.


Membrane Bound Nadh Oxidase Complex Of Micrococcus Lysodeikticus, Karen Ju-Kuang Hsia Apr 1972

Membrane Bound Nadh Oxidase Complex Of Micrococcus Lysodeikticus, Karen Ju-Kuang Hsia

Masters Theses

No abstract provided.


On The Mechanism Of Low-Temperature Termolecular Atomic Recombination, Russell T. Pack, Richard L. Snow, Wesley D. Smith Jan 1972

On The Mechanism Of Low-Temperature Termolecular Atomic Recombination, Russell T. Pack, Richard L. Snow, Wesley D. Smith

Faculty Publications

A simple theory of gas-phase termolecular atomic recombination kinetics is presented which treats the bound-complex (BC) mechanism in a fashion which parallels the Roberts, Bernstein, and Curtiss resonance theory of the energy-transfer (ET) mechanism. The ET rate constant has a low temperature maximum, but the BC rate constant does not. The contributions of the two mechanisms to the low-temperature recombination of hydrogen atoms, with He, Ar, and H2 as third bodies, are estimated and compared. The presence (absence) of a low-temperature maximum in the observable total rate constant is determined by absence (presence) of bound vibrational levels of the hydrogen-third …


Alteration In The Expression Of Compartmentation: In Vitro Studies / D. D. Clarke And S. Berl, Donald Dudley Clarke Phd, Soll Berl Jan 1972

Alteration In The Expression Of Compartmentation: In Vitro Studies / D. D. Clarke And S. Berl, Donald Dudley Clarke Phd, Soll Berl

Chemistry Faculty Publications

Glutamic acid and glutamine are present in unusually large concentrations in brain. The only known enzymatic mechanism which has been reported for the synthesis of glutamine is that catalysed by glutamine synthetase (E.C.6.3.1.2). These amino acids provide a very useful probe for studying precursor-product relationships in brain tissue in vivo. It is evident that the non-steady state situation presented by injection of a single dose of inhibitor followed by a tracer dose of a labelled precursor at some later time-a practice which has been used extensively in previous attempts to clarify the effects of metabolic inhibitors-makes it rather difficult to …


Effects Of Li+ On The Metabolism In Brain Of Glutamate, Glutamine, Aspartate And Gaba From [I-14]Acetate In Vitro / S. Berl And D. D. Clarke Department Of Neurology, College Of Physicians And Surgeons, Columbia University, New York, N.Y. 10032 And Chemistry Department, Fordham University, Bronx, N.Y. 10458 (U.S.A.), Soll Berl, Donald Dudley Clarke Phd Jan 1972

Effects Of Li+ On The Metabolism In Brain Of Glutamate, Glutamine, Aspartate And Gaba From [I-14]Acetate In Vitro / S. Berl And D. D. Clarke Department Of Neurology, College Of Physicians And Surgeons, Columbia University, New York, N.Y. 10032 And Chemistry Department, Fordham University, Bronx, N.Y. 10458 (U.S.A.), Soll Berl, Donald Dudley Clarke Phd

Chemistry Faculty Publications

Guinea pig brain slices were incubated in media in which Li+ replaced part of the Na+. Leakage of glutamic acid, glutamine, aspartic acid and GABA into the media were increased markedly; glutamic acid was most affected. The uptake of [1-14C]acetate was decreased in the presence of Li+. Of the amino acids related to the citric acid cycle the labeling of glutamine was most affected. The presence of 100% O2 counteracts in part the Li+ effects. The results were interpretable on the basis of the compartmentation of citric acid cycle metabolism in brain. It is suggested that the pool of 'transmitter' …


The Structure Of An Ornithine-Containing Lipid From Thiobacillus Thiooxidans, Herman W. Knoche, Jessup M. Shively Jan 1972

The Structure Of An Ornithine-Containing Lipid From Thiobacillus Thiooxidans, Herman W. Knoche, Jessup M. Shively

Department of Biochemistry: Faculty Publications

The structure of an ornithine-containing lipid from Thio-bacillus thiooxidans

has been elucidated. Methanolysis of

the lipid released methyl cis-ll,lZ-methylene-Z-hydroxyoctadecanoate.

Acid hydrolysis of the residue yielded ornithine

and a mixture of fatty acids, the major components of

which were 3-hydroxyhexadecanoic and 2-hexadecenoic

acids. Identification of the 3-hydroxy fatty acid was based

on the thin layer chromatographic mobilities of the acid, its

methyl ester, the methyl ether, and acetate derivatives of its

methyl ester, on the equivalent chain lengths of the derivatives

of the acid and the acid obtained by oxidation of the

natural acid with permanganate, and on mass spectral studies. …


Factors Regulating The Growth Of Algae In Continuous Culture In Diluted Secondary Sewage Treatment Plant Effluent And Subsequent Biodegradability, Edward G. Foree, Caroline P. Wade Jan 1972

Factors Regulating The Growth Of Algae In Continuous Culture In Diluted Secondary Sewage Treatment Plant Effluent And Subsequent Biodegradability, Edward G. Foree, Caroline P. Wade

KWRRI Research Reports

Heterogeneous algal cultures were grown in laboratory continuous culture in continuous flow, completely mixed chemostats in secondary sewage treatment plant effluent diluted to give an ammonia nitrogen concentration of 10 mg/1. Variables were lighting, pH, carbon dioxide availability, and hydraulic residence time.

Optimum growth occurred under pH 7.0, excess CO2, and continuous lighting conditions. The availability of artificially supplied excess CO2 greatly increased the mass (standing crop) at steady-state over that produced under otherwise identical conditions for all residence times studied. For the case of excess CO2 availability, the nitrogen concentration in the algal cells regulated …


Form And Level Of Coumarin In Deer's Tongue, Trilisa Odoratissima, Francis A. Haskins, H. J. Gorz, R. C. Leffel Jan 1972

Form And Level Of Coumarin In Deer's Tongue, Trilisa Odoratissima, Francis A. Haskins, H. J. Gorz, R. C. Leffel

Department of Agronomy and Horticulture: Faculty Publications

Fresh leaves of deer’s tongue contain large quantities (more than 10% of the dry weight, in some cases) of o-hydroxycinnamic acid (o-HCA). Both cis- and trans-o-HCA are present, and both isomers exist in the fresh tissue predominantly as glucosides. Cured deer’s tongue leaves contain relatively high levels of coumarin and lower amounts of o-HCA glucosides. It is probable that during the curing process cis-o-HCA glucoside is hydrolyzed by an endogenous β-glucosidase, and that the liberated cis-o-HCA lactonizes spontaneously to form coumarin.


The Chemical Analysis Of Velella Lata Float, Ralph Lee Gainey Jan 1972

The Chemical Analysis Of Velella Lata Float, Ralph Lee Gainey

University of the Pacific Theses and Dissertations

Everything should be ultimately explainable in terms of the components of which it is composed. In the animal kingdom well over ninety-five percent of all recognized species are invertebrates, a distinction based on connective tissues, though most of our efforts have been directed towards vertebrates for reasons of convenience and closeness to man. Investigation of the various chemicals which make up plants and animals have been diverse, allowing us to get a general picture of what molecules to expect at each state of the evolutionary progression, but for now animal is the information complete, and for invertebrates the information is …


Mathematical Model Of Placental Oxygen And Carbon Dioxide Exchange, Ester P. Hill Dec 1971

Mathematical Model Of Placental Oxygen And Carbon Dioxide Exchange, Ester P. Hill

Loma Linda University Electronic Theses, Dissertations & Projects

This model of placental CO2 and O2 exchange calculates the time course of changes in PCO2, [HCO3-], and [H+] in each of four "compartments" of placental exchange vessels: maternal erythrocytes, maternal plasma, fetal plasma and fetal erythrocytes. The changes in hemoglobin-bound CO2 (carbamate) and oxyhemoglobin contents within the erythrocytes are also calculated, permitting consideration of the Haldane and Bohr effects. Equations were written to represent one-dimensional steady state CO2 and O2 diffusion between concurrent maternal and fetal capillaries and the subsequent hydration, carbamino and oxyhemoglobin reactions. The equations …


Fraction Of Bacterial Ribosomes, Katty S. F. H. Yang Dec 1971

Fraction Of Bacterial Ribosomes, Katty S. F. H. Yang

Masters Theses

No abstract provided.


Report On Water Pollution Problems In Las Vegas Wash And Las Vegas Bay, Environmental Protection Agency Nov 1971

Report On Water Pollution Problems In Las Vegas Wash And Las Vegas Bay, Environmental Protection Agency

Publications (WR)

This report was prepared by the Federal Water- Quality Administration, Pacific Southwest Region, now the Environmental Protection Agency (EPA), Region IX, at the request of the State of Nevada, Department of Health, Welfare, and rehabilitation. In a letter, dated December 5, 1969, this agency asked for technical assistance, as authorized by the Federal Water Pollution Control Act, in developing discharge standards appropriate for Las Vegas Bay, Lake Mead, and the Lower Colorado River. The subsequent study was performed by EPA from January through August, 1970. The establishment of Nevada State Water Quality Standards for these waters will enable responsible officials …


Autoradiographic Studies Of The Distribution Of Serotonin In The Rat Brain, Brent D. Wagstaff Aug 1971

Autoradiographic Studies Of The Distribution Of Serotonin In The Rat Brain, Brent D. Wagstaff

Theses and Dissertations

Serotonin (5-hydroxytryptamine, 5-HT), considered to be a synaptic transmitter within the central nervous system, has been shown to be localized mainly in the paleocortex of the brain. Others have shown disturbances of normal 5-HT metabolism to be associated with mental illness and disease. Attempts to inject tritium labelled 5-HT into cerebrospinal fluid of the rat brain for anatomical localization studies were·made. The following observations were noted, (1) there exists a perivascular space in which fluid flows and distribution is relatively uninhibited as compared to subarachnoid space, (2) the labelled 5-HT penetration of brain tissue parenchyma is restricted and radioactivity is …


Effect Of Exercise On Tissue Concentrations Of Thyroid Hormones And On Thyroxine Degradation Rate In The Rat, William W. Winder Aug 1971

Effect Of Exercise On Tissue Concentrations Of Thyroid Hormones And On Thyroxine Degradation Rate In The Rat, William W. Winder

Theses and Dissertations

Several methods were used to detect changes in thyroid activity and in degradation of thyroxine (T4) in exercising and sedentary control rats. Rats were run in a motor-driven exercise wheel over a three-week period at progressively increasing work loads and then were run 1.5-2 hours per day for 10-14 days before sacrifice. Disappearance of injected T4-125I from plasma was considerably enhanced by exercise. As determined by isotopic equilibration and paper chromatographic methods, T4 concentration was depressed in plasma and elevated in liver of exercised rats. No significant changes in T4 concentration were observed in heart, kidney, or gastrocnemius muscle. Thyroidal …


Histochemical Investigation On The Distribution And Localization Of Digestive Enzymes In The Alimentary Canal Of The Caddis Fly Larvae, Brachycentrus Occidentalis Banks, Walter B. Hollow Aug 1971

Histochemical Investigation On The Distribution And Localization Of Digestive Enzymes In The Alimentary Canal Of The Caddis Fly Larvae, Brachycentrus Occidentalis Banks, Walter B. Hollow

All Master's Theses

A histochemical study of the digestive enzymes of Brachycentrus occidentalis Banks showed that the insect contains the enzymes necessary to utilize the major foods, viz., carbohydrates, lipids and proteins. There appears to be a correlation between the types of digestive enzymes found and the type of food eaten by the larvae. Values of pH for extracts from the different parts of the digestive system were: foregut, 7.6-8.4, midgut, 7.6-8.4, and hindgut, 7.0-7.6. Living micro-organisms in the gut lumen was also shown.