scholarly journals The Effect of Amino Acids and Sulfur Compounds on the Utili-zation of Non-Protein Nitrogen by Rumen Microorganisms in Vitro, with Special Remark to L-Methionine

1974 ◽  
Vol 45 (9) ◽  
pp. 494-501
Author(s):  
Fumio TAKAHASHI ◽  
Masao KAMETAKA ◽  
Makoto KANDATSU
Keyword(s):  
Amino Acids ◽  
Sulfur Compounds ◽  
Protein Nitrogen ◽  
Rumen Microorganisms

A NEW NON-PROTEIN NITROGEN SOURCE FOR RUMINANTS

1969 ◽  
Vol 49 (2) ◽  
pp. 135-141 ◽  
Author(s):  
L. P. Milligan ◽  
A. R. Robblee ◽  
J. C. Wood ◽  
W. C. Kay ◽  
S. K. Chakrabartty
Keyword(s):  
Nitrogen Source ◽  
Dietary Supplement ◽  
Nitrogen Retention ◽  
Feeding Trial ◽  
Short Term ◽  
Protein Nitrogen ◽  
Rumen Microorganisms ◽  
Production Of Ammonia

The preparation of a polymer of urea and furfural containing 23.2% nitrogen is described. This product was converted by rumen microorganisms in vitro to ammonia at a rate approximately one-seventh that of conversion of urea to ammonia. Use of the polymer as a dietary supplement in a feeding trial with lambs improved nitrogen retention over that of unsupplemented controls by 3.45 g of nitrogen retained per day, while an isonitrogenous quantity of supplemental urea improved nitrogen retention by 0.51 g of nitrogen retained per day. The blood urea pattern, throughout the day, of lambs adapted to control, urea-supplemented and urea–furfural polymer-supplemented rations indicated a slow, prolonged production of ammonia from the latter supplement and very rapid, short-term degradation of urea in vivo.

Influence of ammonia concentration on [15N]ammonia uptake andde novosynthesis of different amino acids by mixed rumen microorganisms from the sheep rumenin vitro

1999 ◽  
Vol 1999 ◽  
pp. 212-212 ◽  
Author(s):  
C. Atasoglu ◽  
C.J. Newbold ◽  
R.J. Wallace
Keyword(s):  
Amino Acids ◽  
Protein Synthesis ◽  
De Novo ◽  
Ammonia Concentration ◽  
Dependent Manner ◽  
Microbial Protein ◽  
Concentration Dependent Manner ◽  
Rumen Microorganisms ◽  
Ammonia Uptake

Ammonia is thought to be the main source of nitrogen for protein synthesis by the rumen microorganisms, but peptides and amino acids derived from protein degradation are also incorporated into microbial protein. Recent experiments carried out by Atasogluet al.(1998) demonstrated that preformed amino acids decrease the uptake of ammonia into microbial protein and microbial amino acids in a concentration-dependent manner. However, little is known about how rumen ammonia concentrations affect ammonia uptake into microbial protein. The present study was undertaken to determine the influence of rumen ammonia concentrations on ammonia incorporation andde novosynthesis of individual amino acids by the mixed rumen microorganismsin vitro.

The metabolism of acetate by rumen microorganisms

1974 ◽  
Vol 20 (2) ◽  
pp. 183-185 ◽  
Author(s):  
B. Emmanuel ◽  
L. P. Milligan ◽  
B. V. Turner
Keyword(s):  
Amino Acids ◽  
Fatty Acids ◽  
Nucleic Acids ◽  
Glutamic Acid ◽  
Acetate Metabolism ◽  
Rumen Microorganisms ◽  
Wide Range

Rumen contents were incubated in vitro with acetate-1-14C. Significant amounts of 14C were incorporated into rumen microbial proteins, nucleic acids, and lipids. Serine, glutamic acid, methionine, and cystine were highly labeled, whereas less, or insignificant radioactivity was found in other amino acids. Acetate was incorporated into a wide range of microbial fatty acids. The quantitative significance of acetate metabolism is discussed.

Influence of the concentration of peptides on [15N]ammonia incorporation and de novo synthesis of different amino acids by mixed microorganisms from the sheep rumen in vitro

1998 ◽  
Vol 1998 ◽  
pp. 175-175
Author(s):  
C. Atasoglu ◽  
N.D. Walker ◽  
C.J. Newbold ◽  
R.J. Wallace
Keyword(s):  
Amino Acids ◽  
Protein Synthesis ◽  
De Novo ◽  
De Novo Synthesis ◽  
Rumen Microorganisms ◽  
Microbial Nitrogen ◽  
Sheep Rumen

Ammonia plays an important role in providing N for protein synthesis by rumen microorganisms. Studies using [15N]ammonia or [15N]urea indicate that the proportion of microbial nitrogen derived from ammonia is highly variable, ranging from 18 to 100% (Nolan, 1975; Salter et al., 1979). Peptides and amino acids are also incorporated by rumen microorganisms. They generally stimulate growth (Argyle & Baldwin, 1989), but little is known about the factors which govern the relative proportions of microbial amino acids which are derived from pre-formed amino acids and from ammonia. The present study was undertaken to determine how the concentration of peptides affects ammonia incorporation and the de novo synthesis of individual amino acids by mixed rumen microorganisms.

scholarly journals Incorporation of 15N and 14C into amino acids of bacterial and protozoal protein in the rumen of the cow on urea-rich feed

1979 ◽  
Vol 51 (1) ◽  
pp. 497-505
Author(s):  
Eeva-Liisa Syväoja ◽  
Matti Kreula
Keyword(s):  
Amino Acids ◽  
Rumen Fluid ◽  
Sole Source ◽  
Ammonium Nitrogen ◽  
Limiting Factor ◽  
Nonprotein Nitrogen ◽  
Protein Nitrogen ◽  
Rumen Microorganisms ◽  
Low Protein ◽  
Intracellular Storage

The utilization of the non-protein nitrogen and carbon of feed by rumen microorganisms for the synthesis of protein was studied by administering [U-14C] sucrose and 15NH4Cl to a cow on urea-rich, low-protein feed. By studying the labelling of the protozoa and bacteria and the amino acids isolated from them at intervals up to 48 hours afterwards, it was found that the bacteria synthesized amino acids from nonprotein nitrogen much more rapidly and effectively than the protozoa. Also the labelling of the carbon in the amino acids of the bacteria was more rapid than in the protozoa. In both protozoa and bacteria there was intracellular storage of [14C] sucrose. Of the bacterial amino acids the most vigorous 14C labelling was found in Glu, Arg, Lys, Val and Ala and the weakest labelling in Gly, His and Ser. Of the protozoal amino acids Ala, Asp, Glu, Leu and Lys had the highest labelling and Pro, Gly, His and Phe the lowest. In the bacterial protein the labelling of Pro and Arg was ten times that of the corresponding protozoal amino acids, and Asp, Ser and Ala four times. After the 15NH4Cl dose the half-life of 15N in the rumen fluid was estimated to be 3.3 h. Labelled ammonium nitrogen was about 11 —15 % of the bacterial nitrogen and 2—3 % of the protozoal nitrogen after 1 h. Of the protozoal amino acids Ala, Glu, Val, Asp and Met had the most vigorous labelling, and of the bacterial amino acids Glu, Asp, Ser, He and Tyr. The slowest incorporation of ammonium nitrogen was into His, Pro, Arg and Gly in both bacteria and protozoa. The labelling of the bacterial amino acids was approximately 7—8 times more vigorous than that of the protozoal amino acids. The labelling of Ala was only 4 times, and that of Val, Met and Glu 5 times more vigorous than with protozoal protein. The pathway of histidine synthesis seemed to be restricted in both bacteria and protozoa and therefore may be a limiting factor in protein synthesis, particularly in cows fed urea as the sole source of nitrogen. Of the 14C and 15N label given, 12.9 and 9 % respectively was secreted in the milk during the first 3 days; over the same period the 14C and 15N excreted in the faeces plus urine accounted for 16.9 and 44.3 % respectively of that administered.

Influence of the continuous infusion of peptides, amino acids or urea on rumen microbial activity in sheep receiving grass hay

1992 ◽  
Vol 1992 ◽  
pp. 208-208
Author(s):  
R. Cruz Soto ◽  
C. J. Newbold ◽  
R J. Wallace
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Free Amino Acids ◽  
Free Amino ◽  
Soluble Carbohydrates ◽  
Amino Acid Incorporation ◽  
Rumen Microorganisms ◽  
Grass Hay ◽  
Pure Cultures

Pure cultures of rumen microorganisms usually grow better when amino acids are present, particularly if the amino acids are present as peptides. However, it is less clear how important peptides, compared to free amino acids and ammonia, are to the mixed microbial population of the rumen.In vitromixed cultures suggest that peptides permit more rapid microbial growth on soluble carbohydrates and greater amino acid incorporation than free amino acids (Wright, 1967; Argyle & Baldwin, 1989). However, amino acid N may have no beneficial effect if the energy source is more slowly degraded (Merryet al., 1990). The present experiment was undertaken to assess whether the response of rumen fermentation to additional nitrogen is different depending on whether the N is present as non-protein N, free amino acids, or peptides in sheep receiving a grass hay diet.

scholarly journals ACTION ON FIBROBLASTS OF THE PROTEIN FRACTION OF EMBRYONIC TISSUE EXTRACT

1926 ◽  
Vol 44 (3) ◽  
pp. 387-395 ◽  
Author(s):  
Lillian E. Baker ◽  
Alexis Carrel
Keyword(s):  
Amino Acids ◽  
Protein Fraction ◽  
Nitrogen Concentration ◽  
Embryonic Tissue ◽  
Tissue Extract ◽  
Protein Nitrogen ◽  
Continuous Growth ◽  
Long Time ◽  
Embryo Tissue

The above experiments indicate that the growth-stimulating substance found in embryonic tissue extract, which has been responsible for the continuous growth of fibroblasts in vitro for 14 years, is either protein in nature or closely associated with the protein of the extract and adsorbed by it. If any specific hormone responsible for cell division is present, it is united to the protein or carried along with it in its first precipitation. It seems probable that the tissues utilize this protein for the nitrogen which they build into protoplasm. Whether it is first hydrolyzed before adsorption by the tissues has not been ascertained as yet. It has been shown in other experiments reported in the following paper that the amino acids of the tissue juice do not suffice for the growth of fibroblasts and that hydrolyzed tissue juice is toxic in the same way that a too concentrated mixture of amino acids is toxic. The results of the foregoing experiments may be summarized as follows: 1. Fractionation of embryo tissue juice has shown that it is the protein fraction that contains the activating substance. 2. Tissues continue to grow for a long time in the protein of the extract precipitated by CO2 and at a rate approximately equal to that in the original extract diluted to the same nitrogen concentration. 3. The non-protein nitrogen gives slight stimulation to growth. 4. Purification of the protein by repeated precipitation destroys its growth-promoting properties, but whether this is due to a denaturing of the protein,—which occurs very readily,—or to loss of some substance possibly an enzyme attached to it, has not been ascertained. 5. Preparations of purified proteins from embryonic tissue and egg white have shown no marked nutritive or stimulating action. A number of other pure substances have been tried without effect.

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