Amino acids concentration

A substrate is a substance that is the basic component of an organism. Protein substrates are amino acids, which are essential to life Protein substrates are amino acid preparations that act to promote the production of proteins (anabolism). Amino acids are necessary to promote synthesis of structural components, reduce the rate of protein breakdown (catabolism), promote wound healing, and act as buffers in the extracellular and intracellular fluids. Crystalline amino acid preparations are hypertonic solutions of balanced essential and nonessential amino acid concentrations that provide substrates for protein synthesis or act to conserve existing body protein. 

Order respect to N-Br-amino acid concentration. With the aim of establishing the reaction order with respect to the N-bromoalanine concentration, we have obtained the values of the initial rates for different N-bromoamino acid concentrations with a fixed OH" concentration of 0.23M. The logarithmic plot shows to be a straight line (Fig. 3) with a slope of 1.07 0.03. This means that the decomposition reaction of N-Br-alanine is first order with respect to the N-bromoalanine concentration. From the plot of initial rate against initial N-bromoalanine concentration (Table 1) we can obtain for the pseudofirst order rate constant for N-bromoalanine decomposition a value of 0.0160 0.(XX)4 s-f... 

With a fixed amino acid concentration of 0.02 M, the rate constant proved independent of the concentration of BrO" over the range (0.38-3.09) x 10"3M for N-Br-aminoisobutyric acid and N-Br-Proline. The plot of the obtained initial absorbance values against the initial N-Br-amino acid cone tration shows that Beer s law is obeyed, and the values for the molar absorptivity of the studied N-bromoamino acids are listed in Table 2. 

Since it is possible to differentiate well-preserved from badly preserved collagen through amino acid analysis and gel electrophoresis, it is also possible to determine which bone samples are likely to give erroneous isotopic ratios. At least for 8 C, it should be possible to estimate the in vivo isotopic signature by correcting the changed amino acid concentrations of the collagen extract. This way, a reasonable approach to the reconstruction of pale-odiet should be possible. 

Amino acid concentration. Primary factor that affects pH of the PN admixture the higher the concentration of amino acids, the higher is the amount of calcium and phosphate that can remain in solution (phosphate likely binds with amino acids and less is available to bind with calcium), therefore lowering the risk of calcium-phosphate precipitation. 

Kinetic studies on reducing gas mixtures showed that the concentration of ammonia falls during the reaction, while that of HCN first rises and then stays almost constant. The amino acid concentration increases steadily as the reaction time increases, while the aldehyde concentration remains constant. 

In aqueous solution, the carboxyl group of the activated amino acid reacts with nucleophilic reagents. At lower amino acid concentrations, and if no other nucleophilic compounds are present, hydrolysis takes place to give the neutral compound. 

If no other nucleophiles are present and the amino acid concentration is high enough, the formation of a peptide bond competes with hydrolysis (Orgel, 1989). 

Use of correlation coefficients between amino acid profile data in order to efficiently quantify the degree of similarity between unknown samples and reference proteinaceous materials [7]. The method processes quantitative amino acid concentrations either as per cent relative content (pg g 1 %) or per cent molar content (mol %). A match of more than 0.9 is necessary to ensure a reliable identification of the proteinaceous binder. Table 9.3 reports results obtained on samples coming from the Tintori Collection analysed with two different analytical procedures showing a good correlation with the egg-based binder [96]. 

Liver transplantation has been employed, but the longterm utility is uncertain. Transplantation affords metabolic correction, although relatively minor deviations of amino acid concentration may persist postoperatively. The morbidity of organ transplantation restricts the utility of this approach. 

Wagner, M., Coelho, D. M., Barschak, A. G. et al. Reduction of large neutral amino acid concentrations in plasma and CSF of patients with maple syrup urine disease. J. Inker. Metab. Dis. 23 505-512,2000. 

Amino acids enhance the oxidation peak of Cu(0) obtained with a carbon paste electrode incorporating Cu(II) cyclohexylbutyrate. The increased current is proportional to the amino acid concentration at trace levels in the pM range373. The behavior of such electrodes was investigated for cysteine (115). On scanning potentials in the positive direction, the amino acid is accumulated on the electrode as the Cu(I) complex at +0.90 V vs a standard calomel electrode (SCE), in acetate buffer at pH 4.5 linear range is 2 x 10 9 to 1 x 10-7 M, 1 min accumulation, RSD 3% (n = 5)374,375. 

Jacobson I, Sandberg M, Hamberger A. 1985. Mass transfer in brain dialysis devices-a new method for the estimation of extracellular amino acids concentration. J Neurosci Methods 15(3) 263-268. 

The mechanism of interaction of amino acids at solid/ aqueous solution interfaces has been investigated through adsorption and electrokinetic measurements. Isotherms for the adsorption of glutamic acid, proline and lysine from aqueous solutions at the surface of rutile are quite different from those on hydroxyapatite. To delineate the role of the electrical double layer in adsorption behavior, electrophoretic mobilities were measured as a function of pH and amino acid concentrations. Mechanisms for interaction of these surfactants with rutile and hydroxyapatite are proposed, taking into consideration the structure of the amino acid ions, solution chemistry and the electrical aspects of adsorption. 

Figure 5. Changes of bone collagen amino acids concentrations in acnte lenkemia.

Synthesis of new proteins for growth or repair. This is discussed in Chapter 20. The rate of protein synthesis is a major factor determining the overall rate of amino acid metabolism the higher the rate of synthesis, the lower is the amino acid concentration which reduces the rate of catabolism. 

Figure 8.16 The control of amino acid breakdown and protein synthesis in liver. The factors in regulation are as follows (i) the amino acid concentration in the blood regulates the rate of urea production (Chapter 10) (ii) the amino acid leucine, and the anabolic hormones increase the rate of protein synthesis. Mass action is a term used to describe the effect of concentration of substrate on the reaction rate. The control of protein synthesis is discussed in Chapter 20. Control by leucine has been studied primarily in muscle.

Table 10.3 Effect of increases in blood amino acid concentration on rate of urea production in normal subjects and in patients suffering from cirrhosis of the liver...

The complex that RNA polymerase forms at the promoter site just prior to initiation. Some bacterial promoters require high NTP concentrations to initiate efficient transcription, because this represents a status report on the stores of ATP, UTP, GTP, and CTP needed for RNA synthesis. Nature has evolved a kinetic control device high initiating ATP and GTP concentrations must be present to stabilize an otherwise short-lived polymerase-promoter complex. The reader may also recall that bacterial translation is also tightly controlled, and amino acid starvation leads to ppGpp synthesis, the so-called stringent-response agent that also potently inhibits RNA polymerase. Such kinetic control ensures that NTP and amino acid concentrations are adequate before transcription and translation occur. 

Ruppel, R.A., Kochanek, P.M., Adelson, P.D., Rose, M.E., Wisniewski, S.R., Bell, M.J., et al. (2001) Excitatory amino acid concentrations in ventricular cerebrospinal fluid after severe traumatic brain injury in infants and children the role of child abuse. J Pediatr 138 18-25. 

Ko GN, Korpi ER, Freed WJ, et al. Effect of valproic acid on behavior and plasma amino acid concentrations in chronic schizophrenia patients. Biol Psychiatry 1985 20 199-228. 

FIGURE 10 Aluminum leached from glass containers by amino acids as a function of time at room temperature. Amino acid concentration 0.028 mo 1/L [53]. 

Smith, L. L., Lanza, J. and Smith, G. C. (1990). Amino-acid-concentrations in extrafloral nectar of Impatiens sultani increase after simulated herbivory. Ecology 71 107-115. 

Fig. 2.1.2a-c A Urine amino acids in a patient with cystinuria assayed by an amino acid analyzer (AAA). The indicated peaks are 1 glycine, 2 cystine, 3 ammonia, 4 ornithine, 5 lysine, 6 arginine, i.s. internal standard (S-amino thyl-cysteine). Cystinuria treatment is best followed-up by analyzing an early morning urine specimen, which usually shows the highest amino acid concentrations. b-c see next page... 

Every amino acid concentration in a given body fluid should be matched against the relevant reference range, preferably constructed within the same laboratory environment. However, the reference ranges in the literature are reassuringly consistent, enabling the correct identification of major abnormalities. 

Amino acid Concentration of 10 x stock Concentration in medium ... 

Protein Source and Variety - By choosing a particular protein, one may increase a particular functionality for example, increased sulfur amino acid concentration will enhance gelation of protein ingredients. 

Stillings and Hackler (54) studied the effects of the tempeh fermentation, the action of Rhizopus oligosporus on dehulled, soaked, and sterilized soybeans. The PER of tempeh reached its peak after 24 hours fermentation and then dropped. They ascribed the changes to an increase and then a decrease in tryptophan chemically present. The PER decrease after 24 hours was also attributed to an increased quantity of mold protein, which is lower in sulfur amino acid concentration than the original soy protein. Free amino acids increased markedly, presumably due to the action of the mold proteolytic enzymes. Free methionine was present in the largest amount, and as such was highly available, thus partially accounting for the initial increase in PER. 

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