Which of the following is a benefit of quaternary structure in proteins?

The benefit of quaternary structure in proteins is that subunits can cooperate and be regulated allosterically. Quaternary structure refers to the assembly of multiple polypeptide subunits into a single functional protein complex. This arrangement allows for interactions between the subunits, resulting in cooperative behavior. For example, the binding of a substrate to one subunit can influence the activity of other subunits, which is a key feature in allosteric regulation. This type of regulation is crucial for the control of enzymatic activity and metabolic pathways within the cell, allowing proteins to respond dynamically to changes in their environment.

The other choices highlight concepts that do not accurately reflect the role and benefits of quaternary structure in proteins. The spontaneous folding of proteins is related to tertiary structure, and while some proteins may denature, quaternary structure is not inherently essential for this process. Furthermore, while oligomeric proteins often exhibit biological activity, this statement is overly restrictive as many monomeric proteins can also be biologically active without having a quaternary structure. Thus, the cooperative and regulatory capabilities offered by quaternary structure are indeed significant features that contribute to protein functionality.