Glutamine radioactive

Berl, S., Nicklas, W. J. and Clarke, D. D. Compartmentation of citric acid cycle metabolism in brain labelling of glutamate, glutamine, aspartate and gaba by several radioactive tracer metabolites. J. Neurochem. 17 1009-1015, 1970. 

The mixed lymphocyte reaction (MLR) test was performed in 96-well flat-bottomed microtiter plates. Selected experimental agents were prepared as 10 mM stock solution in DMSO and a 50-fold dilution of this was prepared in RPMI. Serial dilutions were prepared from this subsequent solution and 10 xl of the diluted stock was added to the well to give concentrations in the assay starting at 9.5 xm. In each well was placed 1.5 x 105 donor cells to give a final volume of 0.2 ml RPMI 1640 medium supplemented with 10% human serum, 2mM L-glutamine, and penicillin/streptomycin. Cells were incubated at 37°C in a humidified atmosphere containing 5% carbon dioxide for 120 hours. 3H-Thymidine (0.5 xCi) was added in the final 6 hours of incubation and cell radioactivity levels determined, which were indicative of T-cell proliferation. 

Prusiner, S., and Milner, L. (1970). A rapid radioactive assay for glutamine synthetase, glutaminase, asparagines synthetase, and asparaginase. Anal. Biochem. 37, 429—438. 

For labeled amnion, incubate in proline/glutamine-free DMEM containing 100 Atg/ml ascorbic acid, 100 /zg/ml BAPN, 20% dialyzed foetal calf serum and 2 /rtCi/ml L-[ " C]proline incubate at 37°C on a gyratory shaker for 36 h, wash the membrane exhaustively with PBS (to remove nonincorporated radioactivity) and denude the amnion as above. 

Azaserine, a glutamine antagonist," is known to inhibit the NAD synthetase reaction in which nicotinic acid adenine dinucleotide is converted into NAD with glutamine or ammonia as the nitrogen donor. ° When azaserine or azaleucine was fed to Ricinus communis plants followed by [6- C]quinolinic acid, a marked decrease in incorporation of radioactivity into ricinine was observed with azaleucine, less so with azaserine." Both azaserine and azaleucine were found also to inhibit the incorporation of [6- " C]quinolinic acid into pyridine nucleotide cycle intermediates [in the case of azaserine the conversion of nicotinic acid dinucleotide into nicotinamide adenine dinucleotide (NAD ) was apparently inhibited]. 

B) A. variabilis, (C) C. licheniforme, (D) P. boryanum, and (E) Cloeo-thece sp (12,14), The radioactivity of amino acids in methanolic extracts, subjected to electrophoresis, was quantitated by integration of peaks in radioscans, with corrections applied for decay (A) glutamine, (O) glutamate plus aspartate, (X) dtrulline (or, in the case of C. licheniforme,... 

After 1 s of assimilation of NH4% 77 (Anacystis nidulans) to 97% (C. licheniforme and A. cylindrica) of the in organic compounds extracted with methanol was associated with glutamine (Figure 7). In A. cylindrica, approximately 88% of the associated vsdth glutamine after 3 s of assimilation distilled as amide nitrogen (13). The second major radioactive product of assimilation of was glutamate in all... 

When A. cylindrica was incubated for 120 s in the presence of and ImM azaserine, incorporation of into glutamate was inhibited over 98%, while formation of [ N]glutamine was reduced only 10% (13). radioactivity was not detected in a separate aspartate, citrulline, or arginine peak, when A. cylindrica was incubated with in the... 

Values are means ( standard deviation of the mean) of four experiments and were determined by integration and time correction of peaks of radioactivity from 13N in radioscans after electrophoresis at pH 9.2, in comparison with 13N02 or radioactivity added as determined by scintillation spectroscopy. Asp, i)ar-tate Glu, glutamate Gin, glutamine Cit, citrulline Ala, alanine Arg, arginine. 

The labehng pattern observed after exposure of nodules and/or roots of A. glutinosa to low concentrations of NH4 was distinctly difierent from the pattern observed after exposure of Anabaena cylindrica to [wjjjNg or NH4 (16,17,47) and was somewhat similar to results reported for cultured tobacco cells incubated with NH4 (18). Radioactivity apparently was incorporated independently into the amide position of glutamine and to a lesser extent into glutamate. These results... 

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