The uptake of amino acids by mouse cells (strain LS) during growth in batch culture and chemostat culture: the influence of cell growth rate

1967 ◽  
Vol 168 (1013) ◽  
pp. 421-438 ◽  
Keyword(s):  
Amino Acids ◽  
Growth Rate ◽  
Amino Acid ◽  
Cell Growth ◽  
Glutamic Acid ◽  
Batch Culture ◽  
Amino Acid Uptake ◽  
Essential Amino Acids ◽  
Growth Yields ◽  
Acid Uptake

The uptake of thirteen essential amino acids by mouse LS cells in suspension culture was determined by bacteriological assay methods. Chemostat continuous-flow cultures were used to determine the effect of different cell growth rates on the quantitative amino acid requirements for growth. The growth yields of the cells ( Y = g cell dry weight produced/g amino acid utilized) were calculated for each of the essential amino acids. A mixture of the non-essential amino acids, serine, alanine and glycine increased the cell yield from the essential amino acids. The growth yields from nearly all the essential amino acids in batch culture were increased when glutamic acid was substituted for the glutamine in the medium. The growth yields from the amino acids in batch culture were much less at the beginning than at the end of the culture. The highest efficiencies of conversion of amino acids to cell material were obtained by chemostat culture. When glutamic acid largely replaced the glutamine in the medium the conversion of amino acid nitrogen to cell nitrogen was 100 % efficient (that is, the theoretical yield was obtained) at the optimum growth rate (cell doubling time, 43 h). The maximum population density a given amino acid mixture will support can be calculated from the data. It is concluded that in several routinely used tissue culture media the cell growth is limited by the amino acid supply. In batch culture glutamine was wasted by (1) its spontaneous decomposition to pyrrolidone carboxylic acid and ammonia, and (2) its enzymic breakdown to glutamic acid and ammonia, but also glutamine was used less efficiently than glutamic acid. Study of the influence of cell growth rate on amino acid uptake rates per unit mass of cells indicated that a marked change in amino acid metabolism occurred at a specific growth rate of 0.4 day -1 (cell doubling time, 43 h). With decrease in specific growth rate below 0.4 day -1 there was a marked stimulation of amino acid uptake rate per cell and essential amino acids were consumed increasingly for functions other than synthesis of cell material.

Effects of intramammary arterial infusion of essential amino acids in the lactating goat

1974 ◽  
Vol 41 (1) ◽  
pp. 101-109 ◽  
Author(s):  
J. L. Linzell ◽  
T. B. Mepham
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Milk Protein ◽  
Amino Acid Uptake ◽  
Essential Amino Acids ◽  
Acid Uptake ◽  
Lactating Goats ◽  
Arterial Concentration ◽  
Arterial Plasma ◽  
Amino Acid Concentrations

SummaryExperiments were performed on 3 lactating goats, in which mammary arterial plasma amino-acid concentrations were elevated by the infusion of a solution of essential amino-acids into the carotid artery supplying a transplanted mammary gland. In 2 experiments there were marked elevations in the arterial concentrations of most essential amino acids, but in one case only did this result in significantly increased uptake of amino acids by the gland, the arterio-venous difference being significantly correlated with arterial concentration for all except one amino acid. In the experiment in which increased amino-acid uptake was observed, infusion also resulted in a significantly increased milk yield and increased milk protein yield. The results are discussed in relation to data from other laboratories and lead to the suggestion that milk protein synthesis may be limited by the availability of either methionine or tryptophan.

Effect of 3-O-substituted analogues of D-glucose and D-allose on amino acid uptake by Penicillium sp.

1985 ◽  
Vol 31 (6) ◽  
pp. 513-518 ◽  
Author(s):  
Robert G. Brown ◽  
John M. Embil
Keyword(s):  
Growth Rate ◽  
Amino Acid ◽  
Glutamic Acid ◽  
Extracellular Enzymes ◽  
Amino Acid Uptake ◽  
Acid Uptake ◽  
Production Time ◽  
Penicillium Species ◽  
Penicillium Sp ◽  
Effect On Growth

3-O-Methyl-D-glucose and 3-O-ethyl-D-allose cause an increase in growth rate of two dextranase-producing Penicillium species which is concomitant with an increase in amino acid uptake. In contrast, 3-O-ethyl-D-glucose and 3-O-methyl-D-allose have no effect on growth and inhibit uptake of L-glutamic acid. These results indicate that considerable specificity is involved in the response of Penicillium sp. to O-alkylated sugars and some O-alkylated sugars may reduce production time of extracellular enzymes.

Studies on Contact Inhibition of Growth in the Mouse Fibroblast, 3T3

1973 ◽  
Vol 12 (3) ◽  
pp. 861-873
Author(s):  
A. I. MEISLER
Keyword(s):  
Amino Acids ◽  
Growth Rate ◽  
Amino Acid ◽  
Amino Acid Uptake ◽  
Mouse Fibroblast ◽  
Acid Uptake ◽  
Initial Growth ◽  
Sephadex Column ◽  
Initial Growth Rate ◽  
Inhibition Of Growth

The effect of amino acid concentration on the initial growth rate of the contact-inhibited mouse fibroblasts 3T3 and its SV40-transformed derivative 3T3T has been studied. In medium in which the serum had been passed through a Sephadex column, and the concentration of amino acids lowered 1000-fold, one acid at a time, the growth rate constants were computed. For most of the 16 amino acids studied, the initial growth rate of 3T3 decreased more profoundly than that of 3T3T. The presence in serum of a factor which stimulates amino acid uptake and growth rate of 3T3T is described.

Effects of increased supply of essential amino acids on the metabolism of the isolated perfused guinea-pig mammary gland

1979 ◽  
Vol 46 (1) ◽  
pp. 59-67 ◽  
Author(s):  
Andrew R. Peters ◽  
Stephen Alexandrov ◽  
T. Ben Mepham
Keyword(s):  
Amino Acids ◽  
Protein Synthesis ◽  
Mammary Gland ◽  
Amino Acid ◽  
Guinea Pig ◽  
Amino Acid Uptake ◽  
Essential Amino Acids ◽  
Acid Uptake ◽  
Isoleucine Leucine ◽  
Group 1

SUMMARYThe effects of high rates of infusion of essential amino acids on amino acid uptake by the isolated perfused guinea-pig mammary gland were studied. Infusion of methionine, tyrosine, phenylalanine, histidine and tryptophan (designated group 1) resulted in significant increases in the uptakes of tyrosine, phenylalanine and histidine. Methionine, tryptophan and other essential amino acids were not significantly affected. Infusion of threonine, valine, isoleucine, leucine, lysine and arginine (designated group 2) resulted in significant increases in uptake of all these amino acids. Group 1 amino acid uptake was not significantly affected. Infusion of all the essential amino acids (i.e. groups 1 and 2 together) resulted in significant increases in all their uptakes. Using as index ‘the predicted rate of protein synthesis’, infusion of group 1 and 2 together led to an apparent 27% increase in protein synthesis. The above results are discussed in relation to the control of milk protein synthesis by limiting essential amino acids.

The effect of nitrogen source in the diet on milk production and amino-acid uptake by the udder

1974 ◽  
Vol 41 (3) ◽  
pp. 305-315 ◽  
Author(s):  
R. C. Kellaway ◽  
S. S. E. Ranawana ◽  
J. H. Buchanan ◽  
L. D. Smart
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Nitrogen Source ◽  
Milk Production ◽  
Muscle Protein ◽  
Amino Acid Uptake ◽  
Essential Amino Acids ◽  
Acid Uptake ◽  
Casein Diet ◽  
Friesian Cows

SummaryTwo experiments were carried out with Friesian cows grazing improved winter pastures. In expt 1, 12 cows were fed 6·6kg/d of a barley-based concentrate containing either no N supplement, or supplements of casein, formaldehydeprotected casein or urea which provided 48 g N/d. In expt 2, 12 cows were fed 2·6kg/d of a barley-based concentrate containing either casein, formaldehyde-protected casein or equal mixtures of both, all of which provided 96g N/d.In expt 1, although the production of fat-corrected milk was 7·1% higher and that of total solids 6·1% higher on the protected casein than on the casein diet, production of milk and milk constituents on the control and urea diets were similar to values obtained for cows fed protected casein. In expt 2, milk production and composition were unaffected by treatments.The concentrations of amino acids in jugular plasma and mammary uptake per litre of plasma were not affected by the experimental diets in expt 1, and were unrelated to milk yield in either experiment. In expt 2 the concentrations of glycine, serine and threonine in jugular plasma were significantly higher in the diet in which none of the casein was protected. Mobilization of muscle protein may have been responsible for the elevated levels of glycine in cows fed this diet. Mammary uptakes of essential amino acids in expts 1 and 2 were respectively 47 and 42% of those available, whereas the uptakes of non-essential amino acids were respectively 24 and 17% of those available.An attempt was made to determine the amino acids most likely to limit milk production. Milk:uptake concentration ratios were obtained using our values for amino-acid uptakes and values published previously for the concentration of amino acids in milk. The results of these calculations suggest that the amino acids most likely to limit milk production are threonine, phenylalanine and methionine.

scholarly journals The Regulation and Function of the L-Type Amino Acid Transporter 1 (LAT1) in Cancer

2018 ◽  
Vol 19 (8) ◽  
pp. 2373 ◽  
Author(s):  
Travis Salisbury ◽  
Subha Arthur
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Cancer Cells ◽  
Amino Acid Uptake ◽  
Essential Amino Acids ◽  
Amino Acid Transporter ◽  
Amino Acid Transporters ◽  
Acid Uptake ◽  
Cancer Pathways ◽  
Acid Transporter

The progression of cancer is associated with increases in amino acid uptake by cancer cells. Upon their entry into cells through specific transporters, exogenous amino acids are used to synthesize proteins, nucleic acids and lipids and to generate ATP. The essential amino acid leucine is also important for maintaining cancer-associated signaling pathways. By upregulating amino acid transporters, cancer cells gain greater access to exogenous amino acids to support chronic proliferation, maintain metabolic pathways, and to enhance certain signal transduction pathways. Suppressing cancer growth by targeting amino acid transporters will require an in-depth understanding of how cancer cells acquire amino acids, in particular, the transporters involved and which cancer pathways are most sensitive to amino acid deprivation. L-Type Amino Acid Transporter 1 (LAT1) mediates the uptake of essential amino acids and its expression is upregulated during the progression of several cancers. We will review the upstream regulators of LAT1 and the downstream effects caused by the overexpression of LAT1 in cancer cells.

Gamma-Glutamyl-Amino Acids as Signals for the Hormonal Regulation of Amino Acid Uptake by the Mammary Gland of the Lactating Rat

Neonatology ◽  
1985 ◽  
Vol 48 (4) ◽  
pp. 250-256 ◽  
Author(s):  
Juan R. Viña ◽  
Inmaculada R. Puertes ◽  
Juan B. Montoro ◽  
Guillermo T. Saez ◽  
José Viña
Keyword(s):  
Amino Acids ◽  
Mammary Gland ◽  
Amino Acid ◽  
Hormonal Regulation ◽  
Amino Acid Uptake ◽  
Acid Uptake ◽  
Gamma Glutamyl

scholarly journals Action of growth hormone in vitro on the net uptake and incorporation into protein of amino acids in muscle from intact rabbits given protein-deficient diets

1976 ◽  
Vol 35 (1) ◽  
pp. 1-10 ◽  
Author(s):  
M. R. Turner ◽  
P. J. Reeds ◽  
K. A. Munday
Keyword(s):  
Amino Acids ◽  
Growth Hormone ◽  
Protein Synthesis ◽  
Amino Acid ◽  
De Novo ◽  
Amino Acid Uptake ◽  
Acid Uptake ◽  
Amino Acid Incorporation ◽  
Acid Incorporation

1. Net amino acid uptake, and incorporation into protein have been measured in vitro in the presence and absence of porcine growth hormone (GH) in muscle from intact rabbits fed for 5 d on low-protein (LP), protein-free (PF) or control diets.2. In muscle from control and LP animals GH had no effect on the net amino acid uptake but stimulated amino acid incorporation into protein, although this response was less in LP animals than in control animals.3. In muscle from PF animals, GH stimulated both amino acid incorporation into protein and the net amino acid uptake, a type of response which also occurs in hypophysectomized animals. The magnitude of the effect of GH on the incorporation of amino acids into protein was reduced in muscle from PF animals.4. The effect of GH on the net amino acid uptake in PF animals was completely blocked by cycloheximide; the uptake effect of GH in these animals was dependent therefore on de novo protein synthesis.5. It is proposed that in the adult the role of growth hormone in protein metabolism is to sustain cellular protein synthesis when there is a decrease in the level of substrate amino acids, similar to that which occurs during a short-term fast or when the dietary protein intake is inadequate.

scholarly journals Action of insulin and growth hormone on protein synthesis in muscle from non-hypophysectomized rabbits

1971 ◽  
Vol 125 (2) ◽  
pp. 515-520 ◽  
Author(s):  
P. J. Reeds ◽  
K. A. Munday ◽  
M. R. Turner
Keyword(s):  
Amino Acids ◽  
Growth Hormone ◽  
Protein Synthesis ◽  
Amino Acid ◽  
Incubation Medium ◽  
Amino Acid Uptake ◽  
Diaphragm Muscle ◽  
Acid Uptake

The separate effects of insulin and growth hormone on the uptake and incorporation of five amino acids into diaphragm muscle from non-hypophysectomized rabbits has been examined. Both growth hormone and insulin, when present in the medium separately, stimulated the incorporation into protein of the amino acids, leucine, arginine, valine, lysine and histidine. Insulin also stimulated amino acid uptake, but growth hormone did not. When insulin and growth hormone were present in the incubation medium together, the uptake and incorporation of valine, the only amino acid studied under these conditions, tended to be greater than the sum of the separate effects of the two hormones.

Amino acid uptake regulation by cell growth in cultured hepatocytes isolated from fetal and adult rats

1992 ◽  
Vol 12 (2) ◽  
pp. 135-141 ◽  
Author(s):  
S. Leoni ◽  
S. Spagnuolo ◽  
M. Massimi ◽  
F. Terenzi ◽  
L. Conti Devirgiliis
Keyword(s):  
Amino Acid ◽  
Cell Growth ◽  
Growth Inhibition ◽  
Cell Density ◽  
Amino Acid Uptake ◽  
Growth Stimulation ◽  
Acid Uptake ◽  
Adult Rats ◽  
Dependent Growth ◽  
Differentiation Stage

Amino acid uptake mediated by system A was studied in cultured fetal and adult hepatocytes, subjected to growth stimulation by EGF and insulin, or to growth inhibition by high cell density. The mitogenic stimulation induced a strong transport increase only in fetal cells, while the cell density-dependent growth inhibition, probably mediated by molecules present on adult hepatocyte membranes, provoked the decrease of amino acid uptake only in the adult cells. The results indicate that the different modulation of amino acid transport by cell growth is dependent on the age and the differentiation stage of hepatocytes.

Sign in / Sign up

Export Citation Format

Share Document