Maleate buffer

Reagents Acetylthiocholine iodide or chloride (ATCh, Sigma) maleate buffer 0.1 M, pH = 6.0 sodium citrate CuS04-5H20 distilled H20 potassium ferricyanide commercial acetylcholinesterase or water extract any cholinesterase-containing animal or plant. 

Procedure Cholinesterase activity in analyzed tissue or the matrix (biotest with immobilized AChE) is determined in the incubation media [consisting of substrate ATCh - 34 mmol maleate buffer 0.1 M, pH = 6.0- 6.5 ml sodium citrate 0.1 M - 0.5 ml CuS045H20 0.03M -1.0 ml distilled H20 (or inhibitor in variant with toxin analyzed) -1.0 ml potassium ferricyanide 0.005 M -1 ml.] Volume of incubation media in one test - 400 mcl. As a blank (control sample), a treatment of the exposure without the substrate is used. If inhibitory effects of allelochemical (or any toxin) are analyzed, before the substrate addition the sample was preliminary exposed to allelochemical inhibitor. Two methods for the AChE-biotests may be recommended (i) in microcells ( stationary conditions ) and (ii) in flowing columns-reactors ( dynamic conditions ). 

M Maleate buffer 1.16 g maleic acid and 3.5 g sucrose add deionized glass-distilled water to make 100 mL, and adjust to pH 6.5. 

Uranyl acetate 2 g uranyl acetate and 100 mL maleate buffer add uranyl acetate to the buffer, and adjust to pH 6.0. 

The pH of maximal catalytic activity in maleate buffer was found to be 6.5 compared to 7.5 in tris buffer [cited in Lynn (12). The... 

Ionic strength 0.1 M maleate buffer 25°, 0-alanine-Cu2+ metal ion buffer. 

In a small mortar cooled to OM C, triturate carefully a quantity of the substance to be examined equivalent to about 2500 Ell. Eur, U. of lipolytic activity with 1 mL of cooled maleate buffer solution pH 7.0 R (lipase advent) until a very fine suspension is obtained. Dilute the suspension with cold maleate buffer solution pH 7.0 R. transfer quantitatively to a volumetric flask, and dilute to 100-0 mL with the cold buffer solution. Keep the flask containing the test suspension in iced water during the titration. 

A. 0.1 A/Tris-maleate buffer 100 ml (25 ml stock + 75 ml distilled water)... 

The thermostability of the crude lipase produced by Candida ant-arctica is demonstrated in Figure 1. The remaining activities after incubation for 30 min at different temperatures in 50 irM Tris-maleate buffer, pH 7.0, were measured using olive oil as substrate at 40°C, followed by end-point titration of the liberated fatty acids. 

The thermostabilities of the two enzymes were compared after 30 min of incubation at 75°C in 50 uM Tris-maleate buffer, pH 7.0. 

M potassium maleate buffer (pH 6.0)—Dissolve 29 g of maleic acid and 9.3 g of disodium EDTA 2 H20 in 4 liters of distilled water. Adjust pH to... 

In the author s laboratory, HMM and LMM were obtained by trypsin digestion. LMM was purified by reprecipitation in 75% ethanol and redissolved in 0.5 M KC1-0.05 M tris-maleate buffer, pH 6.5, followed by ultracentrifugation (39). 

LMM, after dialysis against a solution of 0.05 M KC1-0.005 M tris-maleate buffer (pH 6.2), also exhibited a decreased capacity to form well-ordered paracrystals or tactoids as examined by electron microscopy (Figure 5). It is interesting that several half-reconstituted paracrystals (Figure 5b) were found after 6 weeks of frozen storage. 

Fig. 18. Effect of Triton X-100 concentration on the response amplitude of a triglyceride-sensitive FET sensor , 0.4 mM tributylin in 10 mM Tris-maleate buffer O, 0.4 mM triolein in 1 mM Tris-maleate buffer V, 2 mM triolein in the 1 mM buffer. (Reproduced from Nakako et al. (26), with permission.)...

The performance of the triglyceride-sensitive FET biosensor in 0.001 M Tris-maleate buffer soludons, pH 7.0, containing 10% Triton X-100, is shown in Fig. 19. A linear response is obtained up to 1 mM triolein. The triglyceride FET biosensor is useful for the determinadon of triolein over the concentration range of 0-3 mM. 

If phosphate buffer has been used, rinse tissue five times over a period of 1 h in 0.1 A/ maleate buffer containing 3.5% sucrose, pH 6.5, to remove phosphate ions. 

Listed below are some acids and bases that are useful in preparing buffers for enzyme assays. The choice of a particular compound depends on many factors. For example, multicarboxylic acids would be poor choices for reactions involving metal ions as cofactors amino acids may be poor choices for reactions involving amino acids as substrates. The number of buffer components can be kept to a minimum by using an acid and a base to cover the desired region. For example, maleic acid and Tris can be mixed to produce Tris-maleate buffers of pH 5.7 to 8.6 (rather than using maleic acid-NaOH and Tris-HCl). 

Used as cmde extract.Partially enriched by heat treatment of cmde extract at 67 °C for 30 min, ammonium sulphate precipitation (45 % saturation), resolubilisation of the precipitated protein in 50 mM TEA-maleate buffer, pH 7.5, and chromatography on a Sepharose G 200 column. 

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