Cell Language Theory, The: Connecting Mind And Matter

The Bhopalator 137

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

One clear evidence for the existence of the t- and i-protons in mito-

chondria is provided by the two proton pathways or channels known to

operate in the cytochrome c oxidase (D- and K-pathways in Figures 3.39

and 3.40(a) and (b)). For example, the proton entering the oxygen reduc-

tion center of a cytochrome c oxidase from the matrix space (to be

denoted as H+N, where N indicates “negative”) via the D-pathway may

cross the membrane via the PLS (proton loading site) and ends up in the

inter-membrane space (i.e., as H+P, where P indicates “positive”), or may

be diverted to the heme a 3 site to participate in the oxygen reduction reac-

tion becoming a part of the water molecule formed (see Figure 3.40(a)).

In the former case, H+N exits the membrane to become H+P, which hence

would be an example of a t-H+. In the latter case, H+N enters the membrane

through the D-channel and combines with oxygen to form a water mole-

cule at the interior of cytochrome c oxidase, which would make it an

example of i-H+. So here is a clear case of a given proton acting as a t-H+

or as an i-H+, depending most likely on the conformational state of the

membrane enzyme system.

As pointed out in Figure 3.34, one major difference between the che-

miosmotic and conformon models of oxphos is that the chemiosmotic

model involves only one kind of protons (i.e., t-H+) that are directly linked

to both redox reaction and phosphorylation reaction, i.e., produced by

redox reaction and expelled into the intermembrane space later to be con-

sumed by phosphorylation reaction (with the H+/e- stoichiometry fixed to

1), whereas the conformon model postulates the existence of two kinds of

protons (i.e., i-H+ and t-H+), one participating in coupling two or more

intra-membrane enzyme systems moving within the membrane phase

(e.g., Complex IV and F 1 F 0 –ATP synthase) and the other traversing the

membrane and entering the inter-membrane space to create a trans-mem-

brane proton gradient. It was suggested above that the former kind of

protons be referred to as the Williams protons and the latter as Mitchell

proton. The Williams protons and Mitchell protons are closely related to

or identical with what some investigators call the chemical and physical

protons, respectively.

The structural similarity between the intracristae space of mitochon-

dria and the lumen of the thylakoid of chloroplast is shown in Table 3.15.

It is striking to notice that the intermembrane distances in the two

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