Cell Language Theory, The: Connecting Mind And Matter

The Bhopalator 73

“6x9” b2861 The Cell Language Theory: Connecting Mind and Matter

opening and closing of the ion channel/gate while the ligands move through

it to cross the membrane. Three features are noteworthy in the mechanism

shown in Figure 3.10 when compared with that described in [164].

(1) Figure 3.10 is based on a well-known physical principle, i.e., GFCP,

whereas the Fanham et al. mechanism [164] is devoid of any princi-

ple behind the action of the transporter.

(2) Figure 3.10 has eight states of the channel protein and 16 steps under-

lying the selective transmembrane ligand transport, whereas the

Fanham et al. mechanism shows only two states of the transporter

protein.

(3) Thermal fluctuations play an essential mechanistic role in the trans-

membrane ligand movement depicted in Figure 3.10, whereas ther-

mal fluctuations are not explicitly implicated nor mentioned in the

Fanham et al. mechanism.

Since the clockwise operation of the mechanisms in Figure 3.10 is

associated with a positive Gibbs free energy change, i.e., ∆G > 0, the ion

will not move from outside into inside spontaneously. This is because

[X]OUT is less than [X]IN in Eq. (3.8). In contrast, the anticlockwise opera-

tion of the mechanisms in Figure 3.10 is associated with a negative Gibbs

free energy change, i.e., ∆G < 0, and hence the ion will move from inside

to outside, even when [X]OUT is greater than [X]IN, an example of active

transport phenomenon.

Although the direction of the passive transport of ions is completely

determined by the [X]OUT/[X]IN ratio, the direction of active transport is

determined predominantly by the transport protein, because ∆GX in

Eq. (3.8) in this case can be dominated by the ligand binding affinity of

the ion binding site of the active transport protein such that ∆GX° becomes

more negative than can be compensated for by the second term in

Eq. (3.8), resulting in ∆GX being negative on balance. In other words, the

direction of the spontaneous ion movement catalyzed by ion channel pro-

tein will be determined not only by the environment of the protein (i.e.,

the bulk phase concentrations of the ions involved), but also by the con-

formational states of the enzyme (i.e., by the state of the system). It is

convenient to introduce a new term, “systome”, to indicate the

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