Carbon dioxide fixing pathways of glutamic acid synthesis in the rumen

1970 ◽  
Vol 48 (4) ◽  
pp. 463-468 ◽  
Author(s):  
L. P. Milligan
Keyword(s):  
Carbon Dioxide ◽  
Glutamic Acid ◽  
Distribution Pattern ◽  
Acid Synthesis ◽  
Tricarboxylic Acid ◽  
Simultaneous Occurrence ◽  
Rumen Microorganisms ◽  
Glutamate Synthesis ◽  
The Individual

Rumen contents were incubated with NaHCO3-14C and the pattern of incorporation of 14C into glutamic acid was determined. Label was found in C-1, C-2, and C-5 of glutamic acid. This distribution pattern suggested the simultaneous occurrence of the forward tricarboxylic acid (TCA), the atypical forward TCA, and the reverse TCA pathways of glutamate synthesis in the mixed rumen population; these pathways were estimated to account for 63%, 9%, and 28%, respectively, of the glutamate synthesized by pathways entailing CO2 fixation. The contributions of the individual pathways were not influenced by the ration of the host. The significance of these alternate pathways of glutamate synthesis in the metabolism of rumen microorganisms is discussed.

THE METABOLISM OF ACETATE BY WHEAT STEM RUST UREDOSPORES

1964 ◽  
Vol 42 (6) ◽  
pp. 883-888 ◽  
Author(s):  
S. Suryanarayanan ◽  
W. B. McConnell
Keyword(s):  
Carbon Dioxide ◽  
Glutamic Acid ◽  
Tricarboxylic Acid Cycle ◽  
Tricarboxylic Acid ◽  
Water Soluble ◽  
Puccinia Graminis ◽  
Acid Fraction ◽  
Wheat Stem Rust ◽  
Acid Cycle ◽  
Carbon 14

When uredospores of Puccinia graminis var. tritici (race 15B) were incubated at pH 6.2 in phosphate buffer containing either acetate-1-C14or -2-C14, about 12% of the radioactivity was removed from the solution in a period of 3 hours. Respired carbon dioxide contained about 45% and 22% of the carbon-14 taken up as acetate-1-C14and acetate-2-C14, respectively. Incorporation of carbon-14 into spore components was considerably higher with acetate-2-C14than with acetate-1-C14. With either tracer most of the radioactivity in water-soluble spore materials was accounted for in amino acids and neutral substances. Glutamic acid was particularly radioactive and accounted for about 40% of the radioactivity in the amino acid fraction. Incorporation of carbon-14 into the glutamic acid skeleton was consistent with the view that both the tricarboxylic acid cycle and the glyoxalate cycle were functioning.

Physiology of sporeforming bacteria associated with insects. I. Glucose catabolism in vegetative cells

1970 ◽  
Vol 16 (4) ◽  
pp. 243-248 ◽  
Author(s):  
L. A. Bulla ◽  
G. St. Julian ◽  
R. A. Rhodes ◽  
C. W. Hesseltine
Keyword(s):  
Carbon Dioxide ◽  
Bacillus Thuringiensis ◽  
Glutamic Acid ◽  
Tca Cycle ◽  
Tricarboxylic Acid ◽  
Pentose Phosphate ◽  
Acid Oxidation ◽  
Glucose Medium ◽  
Vegetative Cells ◽  
Tentative Evidence

The catabolic pathways for use of glucose in proliferating vegetative cells of Bacillus thuringiensis, B. alvei, B. lentimorbus, and B. popilliae were studied by radiorespirometry. These organisms dissimilate glucose predominately via the Embden–Meyerhof–Parnas pathway and to a lesser extent by the pentose phosphate pathway. Extent of participation of concurrent pathways varied with each organism. Tentative evidence suggests that B. popilliae and B. lentimorbus, grown in a yeast extract – glucose medium, lack a fully operational tricarboxylic acid (TCA) cycle. Dilution of this medium slightly enhanced TCA cycle activity in B. popilliae but had no effect with B. lentimorbus. Radiorespirometric data regarding glutamic acid oxidation also were obtained for each bacterium. All organisms studied except B. lentimorbus were capable of oxidizing glutamic acid to carbon dioxide.

The metabolism of 14C-urea by white spruce seedlings in light and darkness

1973 ◽  
Vol 51 (6) ◽  
pp. 1197-1211 ◽  
Author(s):  
D. J. Durzan
Keyword(s):  
Carbon Dioxide ◽  
Glutamic Acid ◽  
Aspartic Acid ◽  
Urease Activity ◽  
De Novo ◽  
White Spruce ◽  
Acid Synthesis ◽  
Transfer Rna ◽  
Ammonium Ions ◽  
Specific Activities

Weak urease activity was detected in 2-week-old white spruce seedlings. The addition of urea to these seedlings increased urease activity in light compared to darkness. Urease was localized in the cytoplasm mainly in the epidermal cells, and to a lesser extent in vascular tissues and at the shoot apex.In light, the early products of 14C-urea indicated the release of 14C-carbon dioxide and ammonium ions. Radioactivity appeared in the anionic and neutral fractions and then in alanine, serine, and glycine, just as in the fixation of 14C-bicarbonate. By 4 h most radioactivity resided in glutamic acid and alanine. This pattern was associated with increased protein synthesis, and with high levels of free glutamine. Serine, glycine, alanine, and carbamyl aspartic acid had high specific activities.In darkness, radioactivity in alanine persisted, but levels in serine, glycine, and protein were low. Most radioactivity eventually resided in asparagine. Radioactive urea and citrulline were kept at higher levels than in light. Glutamic acid, citrulline, and carbamyl aspartic acid had the greatest specific activities. In light and darkness, carbamyl derivatives were formed more readily from 14C-urea than from 14C-bicarbonate.Carbamyl phosphate was implicated as a precursor of citrulline and arginine as well as for carbamyl aspartic acid. In light, radioactivity was recovered from ribosomal (25, 23, 18, 16, and 5 S) and transfer RNA (4 S). This resided mainly in uracil and cytosine. By contrast, in DNA, radioactivity was recovered mainly from thymine, cytosine, and 5-methylcytosine. In rapidly growing seedlings, urea contributed to de novo nucleic acid synthesis mainly through pyrimidine pathways via carbamyl aspartic acid.

STUDIES ON WHEAT PLANTS USING C14 COMPOUNDS: V. GERMINATION STUDIES WITH LABELLED WHEAT SEEDS

1957 ◽  
Vol 35 (1) ◽  
pp. 1259-1266 ◽  
Author(s):  
W. B. McConnell
Keyword(s):  
Carbon Dioxide ◽  
Amino Acid ◽  
Glutamic Acid ◽  
Active Compound ◽  
Specific Activity ◽  
Tricarboxylic Acid Cycle ◽  
Tricarboxylic Acid ◽  
Acid Cycle ◽  
Carbon 14 ◽  
Wheat Seeds

Radioactive wheat seeds, obtained by injecting acetate-C14 into the stems of the parent plants, were germinated in the absence of light and nutrient and the fate of the carbon-14 was observed. Carbon respired as carbon dioxide had a higher specific activity than any of the major seed components except protein. Variations were found in the patterns by which material was transferred from the kernel to new tissue as reflected in a comparison of the activity of various components. Glutamic acid was the most active compound isolated either from the original seeds or from the new tissues. This observation, together with similarities noted in the intramolecular distribution of carbon-14 in glutamic acid of new tissue and seed residues, indicated that glutamic acid was reutilized for the biosynthesis of seedling protein. Changes in the labelling of glutamic acid during transfer to new tissue are qualitatively in accord with the idea that at least some of the amino acid is used after re-entry into the tricarboxylic acid cycle.

STUDIES ON WHEAT PLANTS USING C14 COMPOUNDS: V. GERMINATION STUDIES WITH LABELLED WHEAT SEEDS

1957 ◽  
Vol 35 (12) ◽  
pp. 1259-1266 ◽  
Author(s):  
W. B. McConnell
Keyword(s):  
Carbon Dioxide ◽  
Amino Acid ◽  
Glutamic Acid ◽  
Active Compound ◽  
Specific Activity ◽  
Tricarboxylic Acid Cycle ◽  
Tricarboxylic Acid ◽  
Acid Cycle ◽  
Carbon 14 ◽  
Wheat Seeds

Radioactive wheat seeds, obtained by injecting acetate-C14 into the stems of the parent plants, were germinated in the absence of light and nutrient and the fate of the carbon-14 was observed. Carbon respired as carbon dioxide had a higher specific activity than any of the major seed components except protein. Variations were found in the patterns by which material was transferred from the kernel to new tissue as reflected in a comparison of the activity of various components. Glutamic acid was the most active compound isolated either from the original seeds or from the new tissues. This observation, together with similarities noted in the intramolecular distribution of carbon-14 in glutamic acid of new tissue and seed residues, indicated that glutamic acid was reutilized for the biosynthesis of seedling protein. Changes in the labelling of glutamic acid during transfer to new tissue are qualitatively in accord with the idea that at least some of the amino acid is used after re-entry into the tricarboxylic acid cycle.

scholarly journals THE FIXATION OF CARBON DIOXIDE IN A PLANT TRICARBOXYLIC ACID SYSTEM

1947 ◽  
Vol 171 (1) ◽  
pp. 445-446 ◽  
Author(s):  
Birgit Vennesland ◽  
Joseph Ceithaml ◽  
Miriam C. Gollub
Keyword(s):  
Carbon Dioxide ◽  
Tricarboxylic Acid ◽  
Acid System ◽  
Fixation Of Carbon Dioxide

A comparison of the compressibilities of some gases with that of nitrogen at pressures below one atmosphere

1950 ◽  
Vol 200 (1061) ◽  
pp. 201-218 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Differential Method ◽  
Linear Extrapolation ◽  
Volume Changes ◽  
Pure Nitrogen ◽  
Molecular Weights ◽  
Nitrous Oxide Oxygen ◽  
The Individual ◽  
Straight Lines ◽  
High Degree

A differential method for comparing the compressibilities of gases at pressures below 1 atm. has been developed in which many of the errors inherent in methods employed previously have been to a large extent eliminated, especially those due to meniscus volume changes and capillary depression. Using pure nitrogen as a standard the low-pressure isothermals of carbon monoxide, carbon dioxide, nitrous oxide, oxygen, ethylene and propane have been determined at a temperature of 22-05° C. The deviations of the individual points from straight lines do not in most cases exceed 2 parts in 100,000. In no case, even with propane, was any curvature in the isotherms detectable. The contention of Moles and other recent workers that the molecular weights of liquefiable gases can be determined to a high degree of accuracy by linear extrapolation is rendered highly probable by this fresh evidence.

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