Hydrophobic effects pockets

The effect of the CF3 substitution on the piQ value was analysed on the basis of comparison between metMb(7-PF) and metMb(meso). The optical study yielded a piTa value of 9.43 + 0.03 for metMb(meso) (Fig. 31), and therefore the substitution of CF3 for the haem peripheral CH3 side-chain at position 7 lowered the pX a value by about 1 pH unit. Ferrihaem in metMb carries a net positive charge, and hence needs to be stabilized through neutralization on electrostatic interaction with nearby polar groups in the hydrophobic haem pocket of the protein. As far as the stability of the ferrihaem in the protein is concerned, the alkaline form is more stable than the acidic one because of neutralization of the cationic character of the... 

The dissolution of HM-HEC in water is coordinate with hydration and expansion of the cellulose backbone as described above. The hydrophobic effect results in the formation of pseudo-micelles along the polysaccharide chain. These pockets of concentrated hydrophobe diminish the internal energy of the polysaccharide, stabilizing the presence of the hydrophobes in the water. These transient cross-links build viscosity and impart a yield value to the solution whereas normal HEC solutions cannot suspend water-insoluble oils, HM-HEC solutions can. 

As was noted in Section 1.1, many protein surfaces are highly solvent exposed compared to the typical active site binding pockets. The prevalence of water molecules increases the local dielectric, decreasing the strength of many non-covalent interactions (including hydrogen bonds and electrostatic interactions). The hydrophobic effect and metal-ligand interactions, however, can be particularly effective in aqueous media. 

Deep-cavity cavitands that dimerize into capsules via the hydrophobic effect, in the presence of a suitable guest molecule and in aqueous solution, have been developed by the Gibb group [110,111], Such complexes possess hydrophilic outer coats, hydrophobic rims that favor self-assembly, and deep hydrophobic pockets (up to 1 nm wide to 2 nm long). They have been used to drive the formation of high-definition assemblies with a number of guest molecules, including steroid and hydrocarbon molecules [112]. Reactions within the capsule (eg, selective oxidation of substrates) and potential applications in hydrocarbon gas separation [111] have been also achieved or demonstrated [113]. 

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