MOLECULAR CHAPERONE DEFINITION FREE

Unfavorable interactions between proteins and osmolytes increases the solvation of the protein with water. Osmolytes exert their chaperoning effects indirectly by changing the interaction of the protein with solvent, rather than through any direct interaction with the protein. Despite being most active at relatively high concentrations, osmolytes don’t display any effects on normal cellular processes – for this reason, they are also commonly referred to as “compatible solutes”. Examples of these include glycerol, trehalose, trimethylamine n-oxide (TMAO), and glycine.

MOLECULAR CHAPERONE DEFINITION FREE

Osmolytes are diverse in chemical structure, and include polyols, sugars, methylamines, and free amino acids and their derivatives. Osmolytes Ĭellular osmolytes are polar small molecules that are synthesized or taken up by cells to maintain the integrity of cellular components during periods of osmotic or other forms of stress. For example, the free amino acid arginine is not classically defined as a chemical chaperone, but it has a well-documented anti-aggregation effect. The parameters that define these groups are not strictly defined, and many small molecules that exert a chemical chaperoning effect do not readily fall into one of these categories. There are many different small molecules that can function to enhance protein stability and folding, many of them can be broadly grouped into large classes based both on their structure and their proposed mechanism of action. Chemical chaperones are used for a range of applications, from production of recombinant proteins to treatment of protein misfolding in vivo. Chemical chaperones are a broad and diverse group of molecules, and they can influence protein stability and polypeptide organization through a variety of mechanisms. Such proteins violate Anfinsen's dogma.Chemical chaperones are a class of small molecules that function to enhance the folding and/or stability of proteins. However, some highly specific 'steric chaperones' do convey unique structural information onto proteins, which cannot be folded spontaneously. In this case, chaperones do not convey any additional steric information required for proteins to fold.

It is for this reason that many chaperones, but by no means all, are also heat shock proteins because the tendency to aggregate increases as proteins are denatured by stress. One major function of chaperones is to prevent both newly synthesised polypeptide chains and assembled subunits from aggregating into nonfunctional structures. The first protein to be called a chaperone assists the assembly of nucleosomes from folded histones and DNA and such assembly chaperones, especially in the nucleus, are concerned with the assembly of folded subunits into oligomeric structures. The common perception that chaperones are concerned primarily with protein folding is incorrect. In molecular biology, molecular chaperones are proteins that assist the non-covalent folding or unfolding and the assembly or disassembly of other macromolecular structures, but do not occur in these structures when the structures are performing their normal biological functions having completed the processes of folding and/or assembly. Freebase Rate this definition: 0.0 / 0 votes

Molecular chaperone definition