Contact dissociation/association, reversible

In a series of works [126,132,246,247] a set of approximate solutions for the contact reactions was suggested. These solutions are based on a hierarchical system of diffusional equations for /(-particle probabilities. The truncation of this system at the second order has led to the so-called multiparticle kernel 3 (MPK3) approximation [126] the third order has given MPK2 theory [132,247], but well before the effort was mounted to truncate this system at the fourth order [246], This earliest attempt, known as MPK1, turned out to be the best for the reversible dissociation/association reaction. It correctly reduces to the limits available for strict investigation ... 

The plasma membrane of the cell is a lipid bilayer sheet in which membrane-bound proteins are embedded. Steps 4B-6B of Figure 1.21 illustrate some events in the production of a membrane-bound protein. After synthesis of the protein, the ribosome on which it was formed dissociates from the membrane but the protein remains bound to the membrane (Step 4B). This binding is mediated by a short stretch of lipophilic amino acids that may occur near the C terminus, as shown in Figure 1.21, or near the N terminus in the case of other proteins. Subsequently, part of the ER membrane forms a bud that breaks off (Step 5B) to form a secretory vesicle (Step 6B). The continued association of the entire membrane-bound protein during the budding process and during subsequent events is maintained by the special lipophilic sequence. Eventually, the secretory vesicle fuses with the plasma membrane in a process that resembles a reversal of Steps 4B-6B. After completion of the insertion of the membrane-bound protein into the plasma membrane, its N terminus is in contact with the extracellular fluid and its C terminus is in contact with the cytoplasm, at least for the protein depicted in Figure 1.21. 

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