The Bhopalator 85“6x9” b2861 The Cell Language Theory: Connecting Mind and MatterY and Y to Z in Figure 3.17. In contrast, the pseudolinkage (see the broken
line in Figure 3.17) is obtained between X and Z if and only if the amount,
and not the activity, of Y remains invariant.
Although Y is truly linked to both X and Z, there is no guarantee that
X and Z will be linked. Under physiologically reasonable conditions (i.e.,
constant temperature and pressure), Wyman has shown that X and Z can
be linked to each other mediated by Y if and only if the amount and not
the chemical activity of Y is held constant. He referred to such a linkage
as the pseudolinkage [175].
It is postulated here that the pseudolinkage can also occur between two
binding sites located in two different macromolecules, M and M′, as long as
these binding sites are truly linked to the common ligand, Y, within each
macromolecule. In other words, ligand X in Complex X·M·Y can be linked
to ligand Z in complex Y·M′ via the common ligand Y if and only if the
amount of Y, not its chemical activity, is kept constant within the phase in
which both these complexes interact, e.g., Complexes I and III in the intram-
embrane phase of the mitochondrial inner membrane mediated by coen-
zyme Q (see Table 3.5). The pseudolinkage obtained within a macromolecule
may be referred to as the first-order pseudolinkage and that operating
between two macromolecules, e.g., between two ETCs in respirasomes,
between an ETC and the PTC (Figure 3.29, Step 2), or between the PTC and
the F 0 F 1 –ATP synthase (also called OSA, oligomycin-sensitive ATPase)Figure 3.17. A diagrammatic representation of the true linkages ( ) and the
pseudolinkage (— — —) of Wyman in polyfunctional macromolecule M [175]. X and Y
are truly linked and so are Y and Z. However, X and Z are not truly linked but can be
pseudolinked if and only if the number of Y, not its activity, can be kept constant.b2861_Ch-03.indd 85 17-10-2017 11:46:22 AM