Aminoacids, long-chain

Polyamides from long-chain aminoacids can be made directly. For example, nylon-11 is synthesized from 11-aminoundecanoic acid... 

There are several reports in the literature on significant acceleration of reaction rates in monolayers. Such increase in reactivity is usually attributed either to enforced juxtaposition of the reactive functional groups in the ordered environment, or to the favourable orientation of the reactive group. Nakahara and coworkers found that long-chain alkane esters of aminoacids polycondense unexpectedly rapidly at the air-water interface, probably because of the close proximity of the amino and ester groups in the monolayer (equation 18)397. 

From the point of view of polymer physics, globular proteins are reminiscent of certain polysoaps, where the hydrophobic part of the chain clusters in a central core, while the hydrophilic residues tend to lie on the outer surface (see Stryer, 1968). This conformation provides both stability and solubility. The crucial difference with polysoaps lies of course in the presence of specific receptors on the protein. A schematic representation for such a receptor is shown in Fig. 2.1. The active site directly involves a number p of aminoacids. These are linked together by comparatively long loops of the peptidic chain. As has been emphasized by Monod (1969), it is of some interest to estimate the minimum size required for each of these loops, when the conformation of the active site itself is prescribed. This should lead in particular to one lower bound for the molecular mass of a globular protein carrying one active site. 

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