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Purification of phospholamban, a 22,000 dalton protein from cardiac sarcoplasmic reticulum that is specifically phosphorylated by cyclic AMP-dependent protein kinase

Description: Very low concentrations deoxycholate (DOC) were used to isolate two proteins from canine cardiac sarcoplasmic reticulum. These two proteins are phospholamban, a 22,000 dalton protein, and the Ca/sup 2 +/ + Mg/sup 2 +/-ATPase, the major protein of the sarcoplasmic reticulum, responsible for the active transport of calcium. The 22,000 dalton protein is first solubilized in a very low concentration of DOC and then subjected to column chromatography. After molecular weight sieving on a Sephadex G-7… more
Date: January 1, 1979
Creator: Bidlack, J. M. & Shamoo, A. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Presence of UV-endonuclease sensitive sites in daughter DNA of UV-irradiated mammalian cells. [3H-thymidine tracer]

Description: Asynchronous Chinese hamster cells were irradiated with 10 Jm/sup -2/ uv radiation and 0.25 to 4 hours later pulse-labeled with (/sup 3/H)thymidine. Cells synchronized by shaking off mitotic and G/sub 1/ cells were irradiated in either the G/sub 1/-phase or S-phase of the cell cycle and pulse-labeled with (/sup 3/H)thymidine in the S-phase. After a 12 to 14 hour chase in unlabeled medium, the DNA was extracted, incubated with Micrococcus luteus uv-endonuclease and sedimented in alkaline sucrose… more
Date: February 1, 1978
Creator: D'Ambrosio, S. & Setlow, R.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, March 1, 1977--May 31, 1977

Description: The degradation of cellulosic biomass continues to focus on the anaerobic thermophile Clostridium thermocellum. When grown on crystalline cellulose (MN300) in batch culture, there is an initial rapid accumulation of reducing sugars but the sugars are rapidly metabolized in later times during the fermentation. When grown on Solka floc with periodic addition of the substrate, there is a continual accumulation of reducing sugars (xylose, glucose, and cellobiose) as well as ethanol and acetic acid … more
Date: June 1, 1977
Creator: Wang, D. I. C.; Cooney, C. L.; Demain, A. L.; Gomez, R. F. & Sinskey, A. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Removal of uv-induced pyrimidine dimers from the replicated and unreplicated DNA of human fibroblasts

Description: Excision repair in uv irradiated human fibroblasts has been examined in portions of DNA replicating after irradiation versus those remaining unreplicated. Two approaches, one using a uv-endonuclease to estimate pyrimidine dimers remaining in DNA, the other using density labeling to measure excision resynthesis, indicate that the extent of repair is the same for both replicated and unreplicated DNA.
Date: January 1, 1978
Creator: Waters, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Biological production of organic solvents from cellulosic wastes. Progress report, September 15, 1976--September 14, 1977

Description: The objectives of this project are to optimize a modular process to convert cellulosic wastes to butanol and other oil-sparing chemicals. Research to date has focused on developing analytical methods, establishing a good data base and improving cellulase yields. Reliable assay methods for the Thermoactinomyces cellulase complex have been developed, measuring glucose and reducing sugar from filter paper and Avicel for total cellulase activity, viscosity change with carboxymethyl cellulose for th… more
Date: June 1, 1977
Creator: Pye, E.K.; Humphrey, A.E. & Forro, J.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks

Description: Progress in studies on the production of reducing sugars and other products by Clostridium thermocellum on cellulosic biomass is reported. The rate of reducing sugar production using corn residue was found to be equal if not greater than on solka floc. Current work is being devoted towards elucidating discrepancies between reducing sugar analysis and high pressure liquid chromatography sugar analysis in order to permit accurate material balances to be completed. Studies are reported in further … more
Date: November 1, 1977
Creator: Wang, D. I. C.; Cooney, C. L.; Demain, A. L.; Gomez, R. F. & Sinskey, A. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Pulmonary macrophage and epithelial cells

Description: Separate abstracts were prepared for the 41 papers presented at the conference. Abstracts of two papers have appeared in previous issues of Energy Research Abstracts. (HLW)
Date: January 1, 1977
Creator: Sanders, C.L.; Schneider, R.P.; Dagle, G.E. & Ragan, H.A. (eds.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, June 1, 1977--August 31, 1977

Description: Studies on the microbial degradation of cellulose biomass continues to be centered around Clostridium thermocellum. The effect of surfactants on growth and cellulase production by C. thermocellum was investigated. The effect of pH on growth and reducing sugar accumulation rate of Clostridium thermocellum on solka floc was evaluated. Activity of extracellular cellulase of Clostridium thermocellum ATCC 27405 was examined using TNP--CMC and Avicel as substrates. The pH optima are 5 and 4.5, respec… more
Date: September 1, 1977
Creator: Wang, D. I. C.; Cooney, C. L.; Demain, A. L.; Gomez, R. F. & Sinskey, A. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Biological production of liquid fuels from biomass. Annual report, September 1, 1978-August 31, 1979

Description: The production of liquid fuels from renewable resources such as poplar wood and lignocellulosic wastes from a refuse hydropulper were studied. The particular scheme being studied involves the conversion of a cellulosic residue, resulting from a solvent delignified lignocellulosic feed, into either high concentration sugar syrups or into ethyl and/or butyl alcohol. The process is aimed at achieving total raw material utilization and maximization of high value by-product recovery. Specific goals … more
Date: January 1, 1979
Creator: Pye, E.K. & Humphrey, A.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Molecular mechanism by which cyclic amp regulates myocardial contractility

Description: From these experiments, it appears that the phosphorylated 22,000 dalton protein does not regulate the transport properties of the ATPase. Instead phosphorylation of the 22,000 dalton protein causes it to become buried in the membrane, transporting Ca/sup 2 +/ into the sarcoplasmic reticulum and thereby, elevating the Ca/sup 2 +/ concentration in the sarcoplasmic reticulum available for release to the myofibrils.
Date: January 1, 1979
Creator: Bidlack, J. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photobiological hydrogen production

Description: Hydrogen production by phototrophic organisms, which has been known since the 1930's, occurs at the expense of light energy and electron-donating substrates. Three classes of organisms, namely, photosynthetic bacteria, cyanobacteria, and algae carry out this function. The primary hydrogen-producing enzyme systems, hydrogenase and nitrogenase, will be discussed along with the manner in which they couple to light-driven electron transport. In addition, the feasibility of using in vivo and in… more
Date: January 1, 1979
Creator: Seibert, M; Lien, S & Weaver, P F
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, December 1, 1978-February 28, 1979

Description: The ongoing progress of a coordinated research program aimed at optimizing the biodegradation of cellulosic biomass to ethanol and chemical feedstocks is summarized. Growth requirements and genetic manipulations of clostridium thermocellum for selection of high cellulose producers are reported. The enzymatic activity of the cellulase produced by these organisms was studied. The soluble sugars produced from hydrolysis were analyzed. Increasing the tolerance of C. thermocellum to ethanol during l… more
Date: February 1, 1979
Creator: Wang, D. I. C.; Cooney, C. L.; Demain, A. L.; Gomez, R. F. & Sinskey, A. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photochemistry and enzymology of photosynthesis

Description: In the first task, a specially designed mass spectrometer system monitors the gas exchange occurring in response to single short flashes of light. This apparatus will be primarily used to study photosystem II donor reactions, such as the photooxidation of hydroxylamine, hydrazine, and hydrogen peroxide. This technique will also be used to study the light-induced exchange of O/sub 2/ and CO/sub 2/ in algae. The second task, biochemical studies, will focus on the role of chloroplast copper in pho… more
Date: July 30, 1979
Creator: Radmer, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies of methylglyoxal synthase: the distribution of enzyme and chemical mechanism of catalysis

Description: Methylgloxal synthase, which catalyzes the conversion of dihydroxyacetone phosphate to methylglyoxal and inorganic phosphate, has been found in several Enterobacteriaceae. The enzyme along with glyoxalase I and II and D-lactate oxidase, therefore, constitute a nonphosphorylated shunt of the normal glycolytic pathway
Date: May 1978
Creator: Yuan, Pau-Miau
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Mechanism Op Action Op P-Hydroxybenzoate Hybrozylase Frompseudomonas Putida. Iii. The Enzyme-Subtrate Complex

Description: The mechanism of action of p-hydroxybenzoate hydroxylase from Pseudomonas putida, strain M-6, has been investigated. The aromatic substrate analogues, benzoate, p-fluorobenzoate, p-chlorobenzoate, p-nitrobenzoate, p-aminobenzoate, and 6-hydroxynicotinate, are found to be competitive inhibitors. This finding differs from the previously reported noncompetitive behavior in a different buffer system. The optical activity of the enzyme-inhibitor complex is studied. From the kinetic and circular dich… more
Date: April 1, 1971
Creator: Teng, Nelson N. H.; Kbtovycz, George; Calvin, Melvin & Hosokawa, Keiichi
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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ISOLEUCYL-tRNA SYNTHETASE OF E. coli B. A RAPID KINETIC INVESTIGATION OF THE L-ISOLEUCINE ACTIVATING REACTION

Description: We have investigated the preequilibrium kinetics of the L-isoleucine activation reaction catalyzed by Ile-tRNA synthetase in the presence of a fluorescent reporter group, 2-p-toluidinylnaphthalene-6-sulfonate, using the stopped-flow technique. It is found that of all the reactants involved, L-isoleucine binds slowest to the enzyme, apparently in a two-step process. The kinetics of the reaction are invariant in the presence of co-reactants, whereas the kinetics for ATP are drastically changed in… more
Date: May 1, 1972
Creator: Holler, E. & Calvin, Melvin
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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MECHANISM OF CARCINOGENESIS OF THE POLYCYCLIC AROMATICHYDROCARBONS

Description: The carcinogenic activity of the benzo[a]pyrene 1, the 7,12-dimethylbenz[a]anthracene 2 and the 3-methylcholanthrene 3 is suggested to be determine by the electrophilic attack of the active oxygen, induced by the hydroxylating enzyme systems, on the most reactive substituting carbon atom(s). The cationic intermediate(s) with the charge mainly localized on a complementary, interrelated position(s) of the hydroxyl substituted position(s) reacts further with the cellular nucleophiles. The electrop… more
Date: August 1, 1970
Creator: Cavalieri, E. & Calvin, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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ISOLEUCYL-tRNA-SYNTHETASE A FLUORESCENCE STUDY OP THE BINDINGPROPERTIES OF THE SYNTHETASE FROM ESCHERICHIA COLI

Description: Fluorescence properties of purified isoleucyl-tRNA-synthetase isolated from E. coli B have been studied. No changes in the quantum yield, energy or polarization of the emission were detected in the presence (either individually or in combinations) of the substrates and cofactors required for activation of L-isoleucine. In 2.5 M urea enzyme activity and intrinsic fluorescence intensity (at 340 nm) each decrease with time, showing similar kinetics and rate constants. The rate of this decay is red… more
Date: November 1, 1970
Creator: Penzer, Geoffrey R.; Bennett, Edward L. & Calvin, Melvin.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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''Aged'' (dense) circulating red cells contain normal concentrations of ATP

Description: A newly-developed technique for determination of the ATP content of individual red cells to the densest, and hence presumably the oldest, cells from normal human blood was applied. It was found that these cells contain normal concentrations of ATP, although the net content of ATP is decreased. The essence of the technique is suspension of red cells in autologous plasma containing luciferin and luciferase, lysis of the cells with a pulse from a laser, and counting of the photoemissions resulting… more
Date: January 1, 1978
Creator: Kirkpatrick, F. H.; Muhs, A. G.; Kostuk, R. K. & Gabel, C. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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In vitro enzymatic studies on the nature and repair of x-ray induced lesions in DNA

Description: Areas studied include: purification and properties of enzyme probes for x-ray induced DNA lesions using E. Coli x-ray endonuclease and S. cerevisiae endonuclease E; use of enzymes probes; and use of physical, chemical and enzymatic probes to quantify x-ray-induced lesions in viruses and cells. (PCS)
Date: January 1, 1979
Creator: Wallace, S. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Carbonic anhydrase levels and internal lacunar CO/sub 2/ concentrations in aquatic macrophytes

Description: Carbonic anhydrase levels were examined in a variety of aquatic macrophytes from different habitats. In general, carbonic anhydrase levels increased across the habitat gradient such that activities were low in submersed aquatic macrophytes and high in emergent macrophytes with floating-leaved and free-floating plants exhibiting intermediate activities. Internal lacunar CO/sub 2/ concentrations were analyzed in relation to carbonic anhydrase activities. There was no correlation between these two… more
Date: January 1, 1979
Creator: Weaver, C.I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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