Conformational behaviour protein folding

Another aspect of these problems is the effect of ions existing in the electrolytic solutions that constitute the fluid component of the cytoplasm. These ions can affect the conformation, interactions and biochemical functions of molecules in the cell. The Hofmeister series, which was first noted in 1888 [95], is invoked in this more modem context. It ranks the relative influence of ions on the physical behaviour of a wide variety of aqueous processes ranging from colloidal assembly to protein folding. The influence of an ion on the properties of macromolecules was initially thought to arise, at least in part, from its capacity of modifying bulk water stmcture. However, recent time-resolved and thermodynamic studies of water molecules in salt solutions show that bulk water structure is not central to the Hofmeister effect. Models are now being developed that take into account direct interactions between ion and macromolecule, and the interactions with water molecules that are operative in the first hydration shell of the macromolecule. 

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