Intrinsic association binding constant

Again, the statistical factors 4, 5, etc., arise because Xr and K-y are intrinsic association binding constants, yet the overall expressions for the complexes requires extrinsic parameters e.g., Kr = [RX]/[R][X] = [R4X2]/[R4X][X] because there are three unfilled sites in the R4X molecule and two in each R4X2 molecule (see also Example 9.12). The fractional saturation Y is again defined by Eq. (9.49) ... 

Fig. 4A presents a Scatchard plot of results obtained by flowing a range of sIL-6R concentrations across the sensor chip and measuring the equilibrium binding response Rp. The slope signifies a intrinsic association equilibrium constant (K x) 2.4x10 (a dissociation constant of 42 nM) which... 

Global compartmental analysis can be used to recover association and dissociation rate constants in some specific cases when the lifetimes are much shorter than the lifetimes for the association and dissociation processes. An example is the study for the binding dynamics of 2-naphthol (34, Scheme 14) with / -CD.207 Such an analysis is possible only if the observed lifetimes change with CD concentration and at least one of the decay parameters is known independently, in this case the lifetime of the singlet excited state of 33 (5.3 ns). From the analysis the association and dissociation rate constants, as well as intrinsic decay rate constants and iodide quenching rate constants, were recovered. The association and dissociation rate constants were found to be 2.5 x 109M-1 s 1 and 520 s 1, respectively.207... 

As a rule, we shall use only intrinsic binding (or association) constants. The relevant experimental data are usually reported in terms of either the thermodynamic dissociation or association constant. The general relation between intrinsic and thermodynamic constants has been discussed in Section 2.3. It will be repeated below for the special cases of this section. 

Intrinsic association or binding constant (reciprocal of k ) for interaction between sites on species i and ... 

Figure 3.24. Calcium binding in 3% /3-casein dispersion at TI2 = 0.14, pH 7.0 and 2°C, as determined by the resin contact time and murexide methods. Apparent maximum number of sites = 11.2 moles of calcium per mole. Apparent intrinsic binding constant = 76.62 liters/mole. (From Jaynes and Whitney 1982. Reprinted with permission of the American Dairy Science Association.)...

Now consider the association of A and B to form oligomers in which the intrinsic binding constants KAX and Kbx have the same values as in the monomers. Since more enzymes apparently exist as isologous dimers than as any other oligomeric form,116 it is appropriate to consider the behavior of such dimers in some detail. Monod et al. emphasized that both... 

Equilibrium-dialysis studies showed two equivalent, sugar-binding sites on each isolectin intrinsic association-constants (Ka ) were 1450 230 M l for binding to D-mannose and 773 126 M I to methyl a-D-glucopyranoside. 453... 

Antigen Injected (mg) Average Intrinsic Association Constants for Binding of c-DNP-Lysine to Anti-DNP Antibodies ... 

Both primary and secondary Ag-Ab interactions may be exploited for analytical purposes, but quantitative bioanalytical methods make extensive use of primary binding interactions. The intrinsic association constant that characterizes antibody-epitope(hapten) binding is called the affinity ... 

The strength of the antigen-antibody complex is called the affinity or avidity. Affinity refers to the intrinsic association constant between an antibody and a univalent antigen, while avidity refers to the overall binding energy between antibodies and a multivalent antigen. We can write the overall binding reaction as... 

Figure 4.20. Strategies for optical detection of intrinsic DNA bends and kinks. (Top) The FRET approach. The energy transfer donor dye (open circle) is covalently attached to the 5 end of a DNA strand. The complementary strand is labeled on its 5 end with an energy transfer acceptor dye (closed circle). The measured energy transfer is a function of the dye-to-dye distance R and should be different for the double helical straight DNA compared with the double helical bent DNA. (Bottom) The noncovalent probe approach. A probe molecule (shaded circle) is allowed to bind to either straight or bent duplex DNA. Equilibrium binding constants or kinetics of association may be monitored via the spectroscopic properties of the probe.

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