Chemical cross-linking and protein–protein interactions—a review with illustrative protocols

The general term “protein–protein” interactions refers to the effects of proteins upon each other. The interactions can arise from co-existence in organized structural arrangements or in transient encounters. The latter are difficult to detect and define. Introduction of specific, stable chemical linkages can establish permanent relationships between what would normally be transiently associated species. The review covers the types and purposes of various linkers, including the comparative advantages of various approaches. The emphasis is on practical applications and thus includes methodology in the form of practical protocols for introducing the linkages and interpreting the outcomes.