Question

Oligomers are often obligate complexes meaning that the free-energy cost of dissociation is high and they exist as oligomers under physiological conditions.

(a) True

(b) False

The question was asked in an online interview.

This interesting question is from Molecular Complementarity topic in portion Predicting the Structure of Protein – Biomolecular Interactions of Bioinformatics

Answer 1

Correct choice is (a) True

For explanation I would say: In some cases biological function is dependent on this. However, many protein interactions are non-obligatory being made/broken according to their environment. These proteins must be independently stable in solution. These are commonly heterodimeric complexes including enzyme inhibitor and antibody-antigen complexes as well as a host of other casual interacting proteins. The hydrophobic effect is often much less dominant and interfaces are more polar in nature partly because of issues relating to protein stability and aggregation. Therefore, hydrophobicity is useful as a guide to molecular complementarity in selective protein-protein interactions.