Isotherms, saturation

Why is myoglobin unsuitable as an O2 transport protein but well suited for O2 storage The relationship between the concentration, or partial pressure, of O2 (PO2) and the quantity of O2 bound is expressed as an O2 saturation isotherm (Figure 6-4). The oxygen-... 

Perform a saturation isotherm to determine the protein gold ratio for each protein and each size colloidal gold (see Note 1). 

Determine the optimal amount of antibody needed by running a saturation isotherm (see Notes 1 and 4). 

From the plateau of the saturation isotherm, the maximal occupancy of the target Bmax can be determined that corresponds to the target concentration in the binding assay. Preferably, the target is used in concentrations of Ttot K, as under these conditions the concentration of TM remains low compared to the concentration of the free marker M and therefore M can be replaced by Mtot for the analysis of the binding experiment [7, 16, 17, 21]. 

Fig. 7.16 Saturation isotherm of NO 711 binding to mGATl-membrane fraction as measured in MS binding experiments. One representative example from a series of identical experiments is shown. Total binding of NO 711 ( lOpg protein according to Bradford). Nonspecific binding (o) measured as binding of NO 711 in the presence of 10 mM GABA. Each data point depicts the mean + SEM from triplicate values.

Fig. 3. A schematic plot of the steady-state initial velocity v, versus the substrate concentration S, illustrating a hyperbolic saturation isotherm (--), positive cooperativity (---), and...

Monod(40) proposed the use of a saturation-isotherm type of equation to relate the growth rate of a micro-organism culture to the prevailing feed concentration. This has become known as the Monod equation and is usually expressed as ... 

Treatment of membrane preparations with digitonin (1-2%) in 100 mM NaCl, 10 mM Tris-HCl pH 7.4 releases 20-30% of the membrane-binding sites in a soluble form that cannot be sedimented at 100,000 xg for 60 min. Saturation isotherms of [3H]spiroperidol as measured by a Sephadex G-50 assay (32) for separation of bound from free ligand reveal a dissociation constant (1C) of 0.5 nM for spiroperidol (not shown). 

This equation should look familiar, because it is functionally identical to the Michaelis-Menten equation of enzyme kinetics. This equation also should make clear the experimental design to be used in determining KD and Bmax using saturation isotherms. We have as the independent variable [E] and as dependent variable B. A successful experiment should permit the estimation of the two biologically meaningful constants KD and 5max. 

Fig.2 a Ultraviolet spectra of N-acetyl-L-phenylalaninyl-L-tryptophanyl methyl ester (APTME) in chloroform (dashed line) and upon saturation with the monomer analog acetic acid (AA). b Saturation isotherm of titrating APTM with AA... 

Figure I Saturation isotherms of [3H]propionyl NPY binding to rat brain membranes. (Reproduced from Mol. Pharmacol. 1995 48,425 432.) (A) Binding of [3H]NPY to brain membranes incubated with increasing concentrations of the radiolabeled peptide. , Total binding , non-specific binding A, specific binding (the difference between total and non-specific binding). For further details, see Daniels et al. (1995a). (B) Scatchard analysis of the saturation experiments. The results represent a typical saturation experiment repeated (n >10) with different membrane preparations = 0.36 0.1 nM, = 306 53 fmol mg-1 protein (mean SE n = 15). The Hill slope for the NPY displacement curve is consistent with a single binding site (nH = 0.99 0.01).

For most applications for food packaging, sorption of water in most hydrophilic polymers can be fit to a saturation isotherm, such as Equation 3. A simplified form would be ... 

Saturation isothermal remanent magnetization (SIRM) The maximum remanence that can be attained in a sample after exposure to a strong magnetic field, generally 1 T. 

CD was utilized to obtain the solvent dependency of the conformation of the cation-lonophore complex as well as Kp s. Saturation Isotherms were plotted from linear computer fits of 1/[cation] versus 1/ArJ the slopes yielded Kjj s while extrapolation of Rq to infinite cation concentration provided the rJ s of the cation-saturated lonophore. It Is Important to note that the cation Itself is a significant vlnclnal moiety, which by virtue of Its charge, polarizability and location with respect to the chromophore of concern, can modify the rotational strength of the chromophore. 

MgCl (10 mM) markedly increased the affinity of malic enzyme for NADP (Kj = 0.38 mM), without significant change in the cooper at ivity (n = 1.57). L-malate not only highly decreased the value to 0.11 mM but also notoriously affected the allosteric behavior, as revealed by an njj value of 0.18 (Table 1). Contrarily to this findings, cooperati-vity was absent in saturation isotherms for NADP obtained from kinetic studies (Figure 2B). From these hyperbolic patterns (n = 1) a K value for NADP of 0.020 mM was calculated (Table 1). ... 

If two substances totally crystallize in a solution, three mass balance equations are formulated. Saturation isotherms, crystallization path, crystal yield and crystal composition can then be presented in a triangular diagram and determined [0.26]. 

Sch] Test heating of slags Saturations isotherms... 

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