Cell Language Theory, The: Connecting Mind And Matter

The Bhopalator 155

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

Figure 3.43 The definition of the three terms appearing in White’s formula for super-

coiled DNA. Lk = linking number, Wr = writhe, and Tw = twist. The mathematical equation

connecting these terms was obtained by J. H. White [225]. See Eq. (3.52).

spontaneously assume a supercoiled form (see Figure 3.43(e)). It is impor-

tant to note that Lk can be altered only through the cutting–twisting–

resealing operation (as described in Figures 3.43(b)–3.43(d)), which is

efficiently carried out by ATP-dependent enzymes known as topoisomer-

ases or DNA gyrase, and that the remaining two parameters, Tw and Wr,

can change in a mutually compensating manner, as shown in (d) and (e).

If the linking number of a relaxed circular DNA duplex is Lk 0 and the cor-

responding number for a supercoiled circular DNA duplex is Lk, then the

linking number difference (usually denoted as a) can be expressed as

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