quaternary protein structure meaning

[Medicine]
The characteristic 3-dimensional shape and arrangement of multimeric proteins (aggregates of more than one polypeptide chain).

Examples

1. A hydrogen-bonding network between subunits has been shown to be important for the stability of the tetrameric quaternary protein structure.
2. In addition to SDS, proteins may optionally be briefly heated to near boiling in the presence of a reducing agent, such as 2-mercaptoethanol ( beta-mercaptoethanol / BME ), which further denatures the proteins by reducing disulfide linkages, thus overcoming some forms of tertiary protein folding, and breaking up quaternary protein structure ( oligomeric subunits ).