Stimulation of the Mu A protein-mediated strand cleavage reaction by the Mu B protein, and the requirement of DNA nicking for stable type 1 transpososome formation. In vitro transposition characteristics of mini-Mu plasmids carrying terminal base pair mutations.

摘要: We have examined the effects of a T----C point mutation at terminal nucleotide Mu ends in mini-Mu plasmid on early steps vitro transposition reaction. These mutations inhibit introduction nicks reaction with A, HU, and integration host factor proteins. The presence either left end or right is sufficient to block nicking both ends, indicating that normally concerted. Addition B ATP, however, dramatically stimulates mutant plasmids carrying one but not ends. data suggest protein mediates its effect through direct interaction A may play role an earlier step process than previously proposed. In B, two products are observed plasmids, normal protein-DNA intermediate (Type 1 complex) which contains abortive product composed free relaxed nicked only wild-type end. Furthermore, stable complexes characteristic first absence when nicked; prerequisite for transpososome assembly.