BIOMOLECULES AND ENZYMES

Detailed explanation-1: -The quaternary structure of a protein is the association of several protein chains or subunits into a closely packed arrangement. Each of the subunits has its own primary, secondary, and tertiary structure. The subunits are held together by hydrogen bonds and van der Waals forces between nonpolar side chains.

Detailed explanation-2: -Quaternary structure is an important protein attribute that is closely related to its function. Proteins with quaternary structure are called oligomeric proteins. Oligomeric proteins are involved in various biological processes, such as metabolism, signal transduction, and chromosome replication.

Detailed explanation-3: -Quaternary structure in proteins is the most intricate degree of organization still considered a single molecule. To be considered to have quaternary structure, a protein must have two or more peptide chains forming subunits. The subunits can be different or identical, and in most cases they are arranged symmetrically.

Detailed explanation-4: -The quaternary structure of this protein complex would be described as a homo-trimer because it is composed of three identical smaller protein subunits (or monomers).

Detailed explanation-5: -The quaternary structure (QS) of a protein is determined by measuring its molecular weight in solution. The data have to be extracted from the literature, and they may be missing even for proteins that have a crystal structure reported in the Protein Data Bank (PDB).