Dynamics of non-covalent biological processes at the molecular level

Strictly speaking, the term "self-assembly" applies to pathways that give-s pontaneously a final product when the correct components are mixed under ap propriate conditions. The pathway must be reversible and the product should be stable at thermodynamic equilibrium. Moreover, the constituent componen ts of the final structure must contain all of the information necessary for correct assembly to occur. Highly organized structures may be formed when many identical molecules aggregate as a direct result of noncovalent bondin g interactions. These interactions give rise to structures biologically imp ortant such as: a) the self-assembly of the DNA double helix from two compl ementary oligonucleotide chains; b) the formation of lipid bilayers to form membranes; c) the protein folding process that produce a biologically acti ve protein molecule; and d) the stereoselectivity present in many receptor molecules. In this report we provide two examples of self-assembly as param eters of the importance to study these phenomena at the molecular level, as well as the techniques currently employed for their study.