scholarly journals The origin of nitrogen incorporated into compounds in the rumen bacteria of steers given protein- and urea-containing diets

1979 ◽  
Vol 41 (1) ◽  
pp. 197-209 ◽  
Author(s):  
D. N. Salter ◽  
K. Daneshvar ◽  
R. H. Smith
Keyword(s):  
Amino Acids ◽  
Rumen Fluid ◽  
Exchange Chromatography ◽  
The Other ◽  
Turnover Rates ◽  
Low Protein ◽  
Protein Amino Acids ◽  
Mixed Bacteria ◽  
N Enrichment ◽  
N Rates

1. Two young Friesian steers fitted with rumen cannulas were each given three different isonitrogenous and isoenergetic diets for successive periods of 2–3 weeks. The diets consisted mainly of straw and tapioca, with the nitrogen supplied mainly as decorticated groundnut meal (DCGM; diet A), in approximately equal amounts of DCGM and urea (diet B), or entirely as urea (diet C).2. At the end of each period on a given diet, part of the dietary urea of a morning feed was replaced by a solution of [15N]urea which was infused into the rumen. Samples of rumen contents were removed just before giving the15N dose and at 1, 3, 5, 7 and 24 h afterwards, concentrations of ammonia and its15N enrichment were determined and samples of mixed bacteria were prepared. Amino acids, ammonia derived mainly from amide groups, and hexosamines were prepared by ion-exchange chromatography of acid-hydrolysates of the bacteria and analysed for15N.3. Approximate estimates of net bacterial N synthesis were made from turnover data for rumen fluid and15N enrichments in rumen fractions. From the determined efficiency of incorporation of urea-N into bacteria recovered at the duodenum, it was calculated that on diets A, B and C respectively 82%, 37% and 0% of the bacterial N was derived from dietary protein or other non-urea sources.4. [15N]urea was converted rapidly to ammonia and the15N then incorporated into bacterial amide-N; it appeared at a slower rate in total bacterial non-amide-N. Rates of incorporation into non-amide-N were highest for glutamic acid, aspartic acid and alanine, and generally lowest for proline (pro), histidine (his), phenylalanine (phe), arginine (arg), methionine (met) and galactosamine. A similar ranking was also generally observed for relative15N abundances (15N atoms %excess in N component ÷15N atoms % excess in total bacterial N) achieved after several hours. Relative15N abundances in his, arg and pro increased with decreasing protein (DCGM) in the diet but those in the other protein amino acids, including the poorly labelled met phe (and its derivative tyrosine) did not.5. It was concluded that different extents of labelling of the amino acids (at least those present mainly in protein) indicated that different amounts of preformed units (amino acids or peptides) were used. When an adequate supply of such units was available (particularly on diet A) pro, arg, his, met and phe were derived in this way to a greater extent than the other amino acids, but whereas synthesis of pro, arg and his increased on the low-protein diet C, that of met and phe did not. Thus met and phe may be limiting for bacterial growth on diets low in protein and high in non-protein-N.6. Differences in the extent of labelling of other bacterial N components may be due to different turnover rates.

Effects of nitrogen rate and genotype on seed protein and amino acid content in canola

2015 ◽  
Vol 154 (3) ◽  
pp. 438-455 ◽  
Author(s):  
Q. S. ZUO ◽  
G. S. ZHOU ◽  
S. F. YANG ◽  
Y. YANG ◽  
L. R. WU ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Protein Content ◽  
Seed Protein ◽  
Amino Acid Content ◽  
The Other ◽  
Seed Protein Content ◽  
Canola Seed ◽  
N Application ◽  
N Rates

SUMMARYCanola (Brassica napusL.) meal is widely used in animal feed as a protein source, and its quality relies on protein and amino acid content. However, little information is available regarding amino acid regulation in canola seed with nitrogen (N) application. The present study is aimed to evaluate the effect of N rate and genotype on canola seed amino acid concentrations under field conditions. A split-plot design comprising four N rates (0, 120, 240 and 360 kg N/ha) and three genotypes differing in seed protein content were used in 2010/11 and 2011/12. The results showed that increasing N rate decreased seed oil content linearly but increased seed protein content in all of the genotypes. The total amino acid concentration and absolute concentrations of individual amino acids in canola seed also improved significantly with the N rates in all of the genotypes. Regarding the proportions of amino acids, a group that included glutamic acid (Glu), proline (Pro) and arginine (Arg) dominated and occupied > 0·30 compared with other amino acids. The ratio of amino acids in this group increased by 8·3% with 360 kg N/ha compared with the control. However, the proportions of the other amino acids showed negative responses to the N rates. The results of regression analysis of the responses of individual amino acids to N rate indicated that Glu, Pro and Arg had a greater improvement potential with application of N fertilizer, as revealed by higher slopes in the linear equations compared with the other amino acids. Additionally, the concentrations of sulphur-containing amino acids, methionine and cysteine, were also a potential target for improving with N application because these are always deficient in major crops. In conclusion, N application cannot only improve seed protein content but also enhance deposition of amino acids such as Glu, Pro and Arg.

scholarly journals Microbial amino acid synthesis and utilization in rats: the role of coprophagy

1996 ◽  
Vol 76 (5) ◽  
pp. 701-709 ◽  
Author(s):  
David Torrallardona ◽  
C. Ian Harris ◽  
Malcolm F. Fuller
Keyword(s):  
Body Weight ◽  
Isotope Ratio Mass Spectrometry ◽  
Acid Synthesis ◽  
Exchange Chromatography ◽  
The Body ◽  
Amino Acid Synthesis ◽  
Low Protein ◽  
N Enrichment ◽  
Fermentable Carbohydrates

Four rats were housed in cages with mesh floors; another four rats were housed in tubular anti-coprophagy cages, in which they could not turn round to reach their own faeces. Both groups were fed for 6 d on a low-protein diet containing fermentable carbohydrates and 15NH4Cl. At the end of the experiment the rats were killed and their carcasses were homogenized, lysine was isolated by ion-exchange chromatography and its 15N enrichment measured by isotope-ratio mass spectrometry. The 15N enrichment in the lysine of the microbial fraction of faeces and the total amount of lysine in the body were also determined in order to estimate the amount of microbial lysine absorbed. The 15N enrichment in body lysine of non-coprophagic rats was not different from that previously measured in rats given unlabelled NH4Cl, but in coprophagic rats it was significantly higher. The daily absorption of microbial lysine by the coprophagic rats accounted for 20·7 (SE 2·55) mg/kg body weight0·75 but was only 0·5 (SE 1·04) mg/kg body weight0·75 for the non-coprophagic rats. This value was not significantly different from zero. The utilization of microbial amino acids via coprophagy resulted in a higher weight gain (adjusted for intake) in the coprophagic group (15·5 g/6 d) than in the non-coprophagic rats (3·1 g/6 d). It was concluded that, in rats, the utilization of microbial lysine occurred exclusively via coprophagy.

PROTEIN TURNOVER IN WHEAT AND SNAPDRAGON LEAVES: PRELIMINARY INVESTIGATIONS

1963 ◽  
Vol 41 (7) ◽  
pp. 969-983 ◽  
Author(s):  
J. A. Hellebust ◽  
R. G. S. Bidwell
Keyword(s):  
Amino Acids ◽  
Protein Turnover ◽  
Soluble Sugars ◽  
Turnover Rates ◽  
Time Intervals ◽  
Protein Nitrogen ◽  
Protein Amino Acids ◽  
Specific Activities ◽  
Wheat Leaves ◽  
Biochemical Differentiation

Detached primary wheat leaves and attached cotyledons and primary leaves of snapdragons were allowed to photoassimilate C14O2 for short periods of time. They were subsequently kept in air and samples were taken at various time intervals and analyzed for protein nitrogen, and amounts and total radioactivities of soluble sugars and amino acids and protein amino acids. A method of estimating protein turnover from these data is discussed. Amounts and specific activities of respired carbon were also determined for wheat leaves.Minimum protein turnover rates of about 0.5 to 1.5% per hour were found in rapidly growing snapdragon leaves and in snapdragon cotyledons. Lower rates were found in detached, non-growing wheat leaves and slowly growing snapdragon leaves. Little contribution could have been made by proteins as substrates for respiration in detached wheat leaves. It is suggested that protein turnover in leaves is mainly associated with growth and biochemical differentiation.

scholarly journals Effects of Dietary Crude Protein Levels on Fecal Crude Protein, Amino Acids Flow Amount, Fecal and Ileal Microbial Amino Acids Composition and Amino Acid Digestibility in Growing Pigs

Animals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2092
Author(s):  
Zhenguo Yang ◽  
Tianle He ◽  
Gifty Ziema Bumbie ◽  
Hong Hu ◽  
Qingju Chen ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Essential Amino Acid ◽  
Crude Protein ◽  
Growing Pigs ◽  
Protein Levels ◽  
Low Protein ◽  
Dietary Crude Protein ◽  
Amino Acids Composition ◽  
Protein Amino Acids

The purpose of this experiment was to evaluate the effects of low protein corn-soybean meal-based diets on fecal CP, amino acid (AA) flow amount, AA digestibility and fecal and ileal microbial AA composition in growing pigs. Eighteen pigs (initial body weight = 30 ± 1.35) were randomly divided into three groups and fed with basal diets with CP levels of 12%, 15% and 18%, respectively. The Lys, Met + Cys, Thr and Trp level in the 12% CP and 15% CP groups is the same as 18% CP group by the addition of four crystalline Lys, Met + Cys, Thr and Trp to the diet. The results showed that with the decrease of dietary CP level from 18% to 12%, the fecal total nitrogen (N), CP and total AA (TAA) flow amount decreased linearly (p < 0.05). Dry matter (DM) digestibility, CP digestibility, TAA digestibility, essential amino acid (EAA) digestibility and non-essential amino acid (NEAA) digestibility increased linearly with the decrease of dietary CP concentration from 18% to 12%. Compared with 18% CP group, the flow amount of Asp, Ser, Glu, Gly, Tyr, Val, Leu and Phe in feces of pigs in the 15% CP group and 12% CP group decreased significantly, while the flow amount of Arg in the 15% CP group was lower than that in the 18% CP group and 12% CP group. The fecal microbial N and AA of the 15% CP group were higher than those of the 18% CP and 12% CP groups. Fecal TAA flow amount decreased linearly with the decrease of the dietary CP levels from 18% to 12%. Fecal TAA and NEAA flow amount also decreased linearly with the decrease of dietary CP level from 18% to 12%. Except for Glu, Gly, Met, Tyr, Thr and Phe, there were significant differences among the three groups in the composition of 17 kinds of AAs in fecal microorganisms. Among the 17 AA compositions of ileal microorganisms, except Tyr and Lys, the other AAs were significantly different among the three groups (p < 0.05)

Amino Acid and Fatty Acid Composition of Tissues of the Dungeness Crab (Cancer magister)

1971 ◽  
Vol 28 (8) ◽  
pp. 1191-1195 ◽  
Author(s):  
W. V. Allen
Keyword(s):  
Skeletal Muscle ◽  
Amino Acids ◽  
Fatty Acids ◽  
Amino Acid ◽  
The Other ◽  
Dungeness Crab ◽  
Cancer Magister ◽  
Storage Organs ◽  
Protein Amino Acids ◽  
Docosahexaenoic Acids

Tissues of the Dungeness crab (Cancer magister Dana) were analyzed for content of total lipid, protein, amino acids, fatty acids, and glucosamine. Ovaries and hepatopancreas were the major lipid storage organs. Gonads (ovaries and testes) and skeletal muscle contained substantially more protein than the other tissues. All tissues except the exoskeleton had balanced amino acid compositions. The exoskeletal protein was deficient in arginine and lysine. Glucosamine was a prominent constituent of the exoskeleton and of the gills and the gastric apparatus. Palmitic, palmitoleic, oleic, eicosapentaenoic, and docosahexaenoic acids were the major fatty acids found in all tissues.

Amino Acid Metabolism in Plants. II. Transamination Reactions of Free Protein Amino Acids in Cell-Free Extracts of Cotyledons and Growing Tissues of Bushbean Seedlings (Phaseolus vulgaris L.)

1972 ◽  
Vol 50 (5) ◽  
pp. 538-542 ◽  
Author(s):  
J. C. Forest ◽  
F. Wightman
Keyword(s):  
Amino Acids ◽  
Protein Synthesis ◽  
Amino Acid ◽  
Amino Acid Metabolism ◽  
Acid Metabolism ◽  
The Other ◽  
Amino Group ◽  
Phaseolus Vulgaris L ◽  
Keto Acids ◽  
Protein Amino Acids

The different transaminase reactions for 22 protein amino acids were investigated in extracts of cotyledons and growing tissues of 8-day-old bushbean seedlings when either α-ketoglutarate, oxaloacetate, pyruvate, or glyoxylate was used as amino group acceptor. The results indicate that both cotyledons and growing tissues exhibited a similar pattern of transaminase activities with respect to the amino acids normally required for protein synthesis. It was found that with the exception of proline, hydroxyproline, and cystine which did not appear to be transaminated, and of serine and threonine which were transaminated only when pyruvate or glyoxylate was provided as the amino group acceptor, all the other 17 amino acids were transaminated to different extents when each of the four keto acids tested was supplied as the amino group acceptor. Glutamic acid, aspartic acid, and alanine were, by far, the best amino group donors and α-ketoglutarate was generally found to be the best amino acceptor. Consideration is given to the number and substrate specificity of the aminotransferases catalyzing the reactions demonstrated in this study.

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.

scholarly journals Genetic code research: a precognition result (II)

2021 ◽  
Author(s):  
Miloje M. Rakočević
Keyword(s):  
Amino Acids ◽  
Genetic Code ◽  
Short Communication ◽  
Number System ◽  
Multiplication Table ◽  
The Other ◽  
Decimal Number ◽  
Other Hand ◽  
Protein Amino Acids

In this second part of the short communication (Ref. 2), we give an argument more in favor of the validity of the precognition status of the final result of my 40 years of genetic code researches. It is shown that the changes in the number of atoms in the system-arrangements of protein amino acids, in relation to the Gaussian number (51) and the Dürer number (34 and 68, respectively), correspond to the changes in the products of number 5 in the Multiplication Table of the decimal number system. On the other hand, with the same changes (in the products of number 5), two unconscious narrations, said in the first part of this communication, correspond one hundred percent.

The effect of ioxynil on the free amino acid and protein content of the leaves of tartary buckwheat and spring wheat

1968 ◽  
Vol 46 (1) ◽  
pp. 89-92
Author(s):  
David Paton ◽  
Saul Zalik
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Protein Content ◽  
Free Amino Acid ◽  
Spring Wheat ◽  
Free Amino ◽  
The Other ◽  
Tartary Buckwheat ◽  
Other Hand ◽  
Protein Amino Acids

The effects of ioxynil on the free amino acid and protein content of the leaves of tartary buckwheat and wheat were compared 2 days after the seedlings were sprayed. Spring wheat showed little change in the overall concentration of either the soluble or protein amino acids. Tartary buck wheat, on the other hand, showed marked changes in the balance between soluble and protein amino acids.

Identification and Stability of Aminopeptidases in Extracts From Bean Seeds

1988 ◽  
Vol 15 (5) ◽  
pp. 613 ◽  
Author(s):  
R Blattler ◽  
U Feller
Keyword(s):  
Amino Acids ◽  
Free Amino ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
The Other ◽  
Gel Chromatography ◽  
Phaseolus Vulgaris L ◽  
Substrate Specificities ◽  
Highly Sensitive ◽  
High Concentrations

Extract from ungerminated bean seeds (Phaseolus vulgaris L. cv. Saxa) was fractionated by gel chromatography on Sephacryl S-200 and by anion exchange chromatography on diethylaminoethyl- Sephacel. Aminopeptidase activities were measured with the following amino acid-p-nitroanilides: phenylalanine, leucine, methionine, proline, alanine, lysine, arginine and glycine. Four forms differing in their substrate specificities were identified: form 1 (liberating alanine, lysine and arginine), form 2 (liberating leucine, methionine, phenylalanine and perhaps also proline), form 3 (liberating glycine) and form 4 (liberating phenylalanine). Form 1 was highly sensitive to 1,10-phenanthroline, while the same concentration of this chelator caused no major effects on the other forms. All aminopeptidases were relatively stable at pH 5.5 in extracts from ungerminated seeds, but the inactivation was accelerated by the addition of cotyledon extract from 8-day-old seedlings. Under such conditions form 3 was most rapidly inactivated followed by forms 1 and 2, while form 4 was less susceptible. The inactivation of the various forms was affected differently by high concentrations of free amino acids. L-Arginine accelerated the inactivation of form 2 and stabilised simultaneously form 3. All forms were protected by L-alanine. Forms 1, 2 and 4 were stabilised by L-serine and by L-proline. Glycine delayed the inactivation of forms 2, 3 and 4.

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