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The nucleolytic ribozymes carry out site-specific RNA cleavage reactions by nucleophilic attack of the 2′-oxygen atom on the adjacent phosphorus with an acceleration of a million-fold or greater. A major part of this arises from concerted general acid–base catalysis. Recent identification of new ribozymes has expanded the group to a total of nine and this provides a new opportunity to identify sub-groupings according to the nature of the general base and acid. These include nucleobases, hydrated metal ions, and 2′-hydroxyl groups. Evolution has selected a number of different combinations of these elements that lead to efficient catalysis. These differences provide a new mechanistic basis for classifying these ribozymes.

Disordered proteins often perform functions that depend on binding to other molecules, typically other proteins or DNA. The differences found in comparison with the union of proteins with tertiary structure, such as the classic example of the key and the lock for the functioning of enzymes, are substantial, therefore the physical-chemical factors that determine the mechanism of binding in disordered proteins They are currently under intense study. The binding processes of disordered proteins are characterized by low affinity, that is, the junctions are generally weak, but instead are highly specific. During binding the disordered protein usually acquires structure and fixes its conformation

Denaturation causes various effects on the protein:

changes in the hydrodynamic properties of the protein: it increases viscosity and decreases the diffusion coefficient

a drastic decrease in its solubility, since hydrophobic residues inside appear on the surface

loss of biological properties

A denatured protein has only its primary structure. For this reason, in many cases, denaturation is reversible since it is the primary structure that contains the necessary and sufficient information to adopt higher levels of structuring. The process by which the denatured protein recovers its native structure is called renaturation. This property is very useful during protein isolation and purification processes, since not all proteins react in the same way to a change in the environment where it is dissolved. In some cases, denaturation leads to total loss of solubility, thereby precipitating protein. The formation of strongly hydrophobic aggregates prevents their renaturalization, and makes the process irreversible.