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The Calyptogena magnifica chemoautotrophic symbiont genome

Description: Chemoautotrophic endosymbionts are the metabolic cornerstone of hydrothermal vent communities, providing invertebrate hosts with nearly all of their nutrition. The Calyptogena magnifica (Bivalvia: Vesicomyidae) symbiont, Candidatus Ruthia magnifica, is the first intracellular sulfur-oxidizing endosymbiont to have its genome sequenced, revealing a suite of metabolic capabilities. The genome encodes major chemoautotrophic pathways as well as pathways for biosynthesis of vitamins, cofactors, and all 20 amino acids required by the clam.
Date: March 1, 2007
Creator: Newton, I.L.; Woyke, T.; Auchtung, T.A.; Dilly, G.F.; Dutton,R.J.; Fisher, M.C. et al.
Partner: UNT Libraries Government Documents Department

Human folate metabolism using 14C-accelerator mass spectrometry

Description: Folate is a water soluble vitamin required for optimal health, growth and development. It occurs naturally in various states of oxidation of the pteridine ring and with varying lengths to its glutamate chain. Folates function as one-carbon donors through methyl transferase catalyzed reactions. Low-folate diets, especially by those with suboptimal methyltransferase activity, are associated with increased risk of neural tube birth defects in children, hyperhomocysteinemic heart disease, and cancer in adults. Rapidly dividing (neoplastic) cells have a high folate need for DNA synthesis. Chemical analogs of folate (antifolates) that interfere with folate metabolism are used as therapeutic agents in cancer treatment. Although much is known about folate chemistry, metabolism of this vitamin in vivo in humans is not well understood. Since folate levels in blood and tissues are very low and methods to measure them are inadequate, the few previous studies that have examined folate metabolism used large doses of radiolabeled folic acid in patients with Hodgkin�s disease and cancer (Butterworth et al. 1969, Krumdieck et al. 1978). A subsequent protocol using deuterated folic acid was also insufficiently sensitive to trace a physiologic folate dose (Stites et al. 1997). Accelerator mass spectrometry (AMS) is an emerging bioanalytical tool that overcomes the limitations of traditional mass spectrometry and of decay counting of long lived radioisotopes (Vogel et al. 1995). AMS can detect attomolar concentrations of 14 C in milligram-sized samples enabling in vivo radiotracer studies in healthy humans. We used AMS to study the metabolism of a physiologic 80 nmol oral dose of 14 C-folic acid (1/6 US RDA) by measuring the 14 C-folate levels in serial plasma, urine and feces samples taken over a 150-day period after dosing a healthy adult volunteer.
Date: March 25, 1999
Creator: Arjomand, A; Bucholz, B A; Clifford, A J; Duecker, S R; Johnson, H; Schneider, P D et al.
Partner: UNT Libraries Government Documents Department

Food values in common portions.

Description: Provides composition tables for a variety of foods, and a table of daily dietary allowances for adults and children.
Date: April 1951
Creator: United States. Bureau of Human Nutrition and Home Economics.
Partner: UNT Libraries Government Documents Department


Description: A review of the theories of electron paramagnetic resonance in biology is presented, including a discussion of the nature of the physical observation, followed by examples of materials of biological interest. Iq discussing these examples, information is presented in terms of the nature of the starting material under observation rather than the nature of the magnetic entities observed. The examples proceed from the simpler molecules of biological interest (metabolites, vitamins, cofactors) into the more complex materials (polymers, proteins, nucleic acids) toward cellular organelles (mitochondria, chloroplasts) and, finally, to whole cells, organisms and organs. The observation of photoinduced unpaired electrons in photosynthetic material is described and the various parameters controlling it are discussed. The basic observation is interpreted in terms of a primary photophysical act of quantum conversion.
Date: August 15, 1961
Creator: Androes, G.M. & Calvin, Melvin.
Partner: UNT Libraries Government Documents Department

Ascorbic acid inhibits replication and infectivity of avian RNA tumor virus

Description: Ascorbic acid, at nontoxic concentrations, causes a substantial reduction in the ability of avian tumor viruses to replicate in both primary avian tendon cells and chicken embryo fibroblasts. The virus-infected cultures appear to be less transformed in the presence of ascorbic acid by the criteria of morphology, reduced glucose uptake, and increased collagen synthesis. The vitamin does not act by altering the susceptibility of the cells to initial infection and transformation, but instead appears to interfere with the spread of infection through a reduction in virus replication and virus infectivity. The effect is reversible and requires the continuous presence of the vitamin in the culture medium.
Date: April 1, 1980
Partner: UNT Libraries Government Documents Department

Milk for the family.

Description: Provides advice for selecting, storing, and using milk products. Explains the nutritive value of milk.
Date: 1940
Creator: Carpenter, Rowena Schmidt, b. 1894
Partner: UNT Libraries Government Documents Department


Description: Vitamin B/sub 12/, labeled with Co/sup 60/ having a specific activity of 1.0 mu C/ mu g, was administered to 18 patients in the late stages of malignandt diseases. Death occurred 11 hr to 695 days after Co -- B/sub 12/ administration. Data are presented on the distribution of Co -- B/sub 12/ in tissues andd organds obtained at post-mortem examination. From 16.8 to 108% was in the liver, with lesser amounts in the othef organds and tissues. Variations resulted from the route of administration, disesse state, and interval between administration and death. (C.H.)
Date: January 1, 1962
Creator: Meyer, L.M.; Driscoll, D.H.; Cronkite, E.P. & Bertcher, R.W.
Partner: UNT Libraries Government Documents Department


Description: This report covers the following titles: (1) Synthesis of compounds from {sup 14}CO{sub 2} by Chlorella in the dark following preillumination; (2) The effect of oxygen on formation of glycolic acid and other products during photosynthesis by Chlorella; (3) Phosphatase action on phosphoglycolic, 3-phosphoglyceric, and phosphoenolpyruvic acids in spinach chloroplast fragments in the presence and absence of high concentrations of methanol; (4) Absorption spectra of scattering samples. I. An evaluation of three different spectrophotometric techniques using Chlorella; (5) Absorption spectra of scattering samples. II. Scattered transmission spectra of leaves, chloroplasts, and quantasomes of spinach; (6) The effect of sonication of spinach chloroplasts on photosynthetic phosphorylation; (7) Concerning the occurrence of {alpha},{alpha}-tocopherol and {alpha}-tocopherylquinone in chloroplasts and quantasomes; (8) Effects of ultraviolet and gamma radiation of thymine in frozen aqueous solution and in the solid state; and (9) A rapid method for the identification of small quantities of lipid-soluble vitamins and quinones in biological material.
Date: September 26, 1962
Partner: UNT Libraries Government Documents Department

Concentration of Plutonium by Cation Exchange--Stabilization of Pu(III) in Nitric Acid

Description: A study to define the effectiveness limits of sulfamic acid and to discover other better stabilizers for Pu(III) is described. Ascorbic and isoascorbic acids, used in conjunction with sulfamic acid reduced Pu(IV) to stable Pu(III) in nitric acid. Aminoguanidine sulfate also retarded the oxidation of Pu(III) but did not reduce Pu(IV). (J.R.D.)
Date: February 1, 1959
Creator: Tober, F. W. & Russel, E. R.
Partner: UNT Libraries Government Documents Department


Description: Our work focuses on the use of microorganisms to recover petroleum hydrocarbons that remain entrapped after current recovery technologies reach their economic limit. Capillary forces between the hydrocarbon and aqueous phases are largely responsible for trapping the hydrocarbons in the pores of the rock and large reductions in the interfacial tension between the hydrocarbon and aqueous phases are needed for hydrocarbon mobilization (1-3, 10, 11). Microorganisms produce a variety of biosurfactants (4), several of which generate the ultra low interfacial tensions needed for hydrocarbon mobilization (4, 5, 8). In particular, the lipopeptide biosurfactant produced by Bacillus mojavensis strain JF-2 reduces the interfacial tension between hydrocarbon and aqueous phases to very low levels (<0.016 mN/m) (8) (9). B. mojavensis JF-2 grows under the environmental conditions found in many oil reservoirs, i. e., anaerobic, NaCl concentrations up to 80 g l{sup -1}, and temperatures up to 45 C (6, 7), making it ideally suited for in situ applications. However, anaerobic growth of B. mojavensis JF-2 was inconsistent and difficult to replicate, which limited its use for in situ applications. Our initial studies revealed that enzymatic digests, such as Proteose Peptone, were required for anaerobic growth of Bacillus mojavensis JF-2. Subsequent purification of the growth-enhancing factor in Proteose Peptone resulted in the identification of the growth-enhancing factor as DNA or deoxyribonucleosides. The addition of salmon sperm DNA, herring sperm DNA, E. coli DNA or synthetic DNA (single or double stranded) to Medium E all supported anaerobic growth of JF-2. Further, we found that JF-2 required all four deoxyribonucleosides (deoxyadeonosine, deoxyguanosine, deoxycytidine and thymidine) for growth under strict anaerobic conditions. The requirement for the deoxyribonucleosides did not occur under aerobic growth conditions. DNA was not used as a sole energy source; sucrose was required for anaerobic growth and biosurfactant production in DNA-supplemented Medium E. ...
Date: May 31, 2004
Creator: McInerney, M.J.; Folmsbee, M. & Nagle, D.
Partner: UNT Libraries Government Documents Department

Development of biological coal gasification (MicGAS process). Nineth quarterly report, [July--September 1992]

Description: Laboratory scale studies examining biogasification of Texas lignite at various coal solids loadings have been completed. Bench scale bioreactors are currently being used to scale up the biogasification process to higher coal solids loadings (5% and 10%) Specific observations reported this quarter are that methane production was not curtailed when B-vitamin solution was not added to the biogasification medium and that aeration of Mic-1 did not sufficiently oxidize the medium to eliminate strict anaerobic bacteria including methanogens.
Date: October 30, 1992
Partner: UNT Libraries Government Documents Department

Human Vitamin B12 Absorption and Metabolism are Measured by Accelerator Mass Spectrometry Using Specifically Labeled 14C-Cobalamin

Description: There is need for an improved test of human ability to assimilate dietary vitamin B{sub 12}. Assaying and understanding absorption and uptake of B{sub 12} is important because defects can lead to hematological and neurological complications. Accelerator mass spectrometry (AMS) is uniquely suited for assessing absorption and kinetics of {sup 14}C-labeled substances after oral ingestion because it is more sensitive than decay counting and can measure levels of carbon-14 ({sup 14}C) in microliter volumes of biological samples, with negligible exposure of subjects to radioactivity. The test we describe employs amounts of B{sub 12} in the range of normal dietary intake. The B{sub 12} used was quantitatively labeled with {sup 14}C at one particular atom of the DMB moiety by exploiting idiosyncrasies of Salmonellametabolism. In order to grow aerobically on ethanolamine, S. entericamust be provided with either pre-formed B{sub 12} or two of its precursors: cobinamide and dimethylbenzimidazole (DMB). When provided with {sup 14}C-DMB specifically labeled in the C2 position, cells produced {sup 14}C-B{sub 12} of high specific activity (2.1 GBq/mmol, 58 mCi/mmol) and no detectable dilution of label from endogenous DMB synthesis. In a human kinetic study, a physiological dose (1.5 mg, 2.2 KBq/59 nCi) of purified {sup 14}C-B{sub 12} was administered and showed plasma appearance and clearance curves consistent with the predicted behavior of the pure vitamin. This method opens new avenues for study of B{sub 12} assimilation.
Date: January 26, 2006
Creator: Carkeet, C; Dueker, S R; Lango, J; Buchholz, B A; Miller, J W; Green, R et al.
Partner: UNT Libraries Government Documents Department