Cell Language Theory, The: Connecting Mind And Matter

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

conformons stored in myosin. In Figure 3.49, state a, one molecule of ATP

is bound to S-1 and myosin is in its ground state (as symbolized by a

relaxed spring). Brownian motions (also called thermal fluctuations) bring

S-1 close to the myosin-binding site on the thin filament (see the upper

bar with two indentations) that is located on the Z-line side of myosin (see

(a) → (b)). Upon binding actin, myosin catalyzes the phosphoryl group

(or phosphoron) transfer from the bound ATP to a hypothetical phos-

phoryl group acceptor X located in S-1 (see (b)). The exergonic nature of

this reaction enables the following two events to take place: (i) the genera-

tion of a charge on myosin which increases the actin-binding affinity and

(ii) the paying back of the thermal energy borrowed from the environment

to extend the S-2 subfragment in going from State (a) to State (b). Actin

and myosin are now tightly coupled electrostatically and mechanical

energy is stored in myosin (which corresponds to State 3 in Figure 3.48(d)).

As S-2 relaxes, the thin filament is pushed toward left as indicated by the

arrow in State (b). When S-2 contracts to a critical distance, through allos-

teric interactions, the phosphoryl group in the myosin head (i.e., S-1) is

thought to be transferred from X to Y (which could well be bound H 2 O)

(see State (c)) and the actin-binding affinity is drastically reduced so that

myosin becomes detached from the thin filament (see (c) → (d)), thus

completing one contractile machine cycle.

It is known that one ATP split is capable of moving the thin filament

by a maximum of about 100 Å or 10 nm [234]. This finding was the basis

for the assumption that one turnover of ATP hydrolysis cause myosin to

be displaced by about 100 Å (or 10 nm) in two steps, from States (b) to

(c) (accompanied by the release of ADP from myosin) and from states c

to d (associated with the release of Pi from the same). The sequential

releases of ADP and Pi were postulated on the basis of the analogy drawn

between the electron and the highly unstable phosphoryl group, PO 3 - , i.e.,

the phosphoron [6]. Just as the electron flow from carrier A to carrier B in

Figure 3.30 leads to the generation of conformons (see the cocked spring

stabilized by two opposite charges at state c), so it was thought plausible

to generate conformons in myosin by transferring the phosphoron from

ATP to a hypothetical phosphoron carrier X and then to another phospho-

ron carrier, Y, thereby generating two conformons, each carrying about 8

kcal/mol of free energy. Thus, it was assumed that in States (b) and (c) in

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