[Native globular and native partially or completely disordered proteins. Folding, supramolecular complex formation and aggregation].

ABSTRACT

Recently it became evident that proteins can perform their function not only in globular state but also in partially or completely disordered state. The majority of globular proteins are enzymes which function is strictly determined. Regulation and signaling proteins participating in interconnection with variety of partners must have much more lability, and macromolecules of such proteins are mainly in partially or completely disordered state. The aim of this work was to describe from the unified viewpoint in the frame of energy landscape model the existence of native globular, native partially or completely disordered proteins, formation of intermolecular complexes with various partners, formation of amorphous aggregates and amyloid fibrils. Compact globular proteins are formed if polypeptide chain provides strong intramolecular interconnections. The ability of polypeptide chain to fold in a compact globule depends on the relation of hydrophobic and charged aminoacids in its composition. Many partially or completely disordered proteins can form compact structure in complexes with their partners, which are composed by intermolecular interactions of polypeptide chains of protein and its partner. Intermolecular interaction of proteins can lead to formation associates, amorphous aggregates, amyloid and amyloid-like fibrils. The requisite condition of such contact formation is the availability of hydrophobic clusters of polypeptide chain exposed to the solution. That is why aggregation of partially or completely disordered proteins is more favorable in comparison with globular proteins.