Mutations in the carboxy‐terminal part of IS30 transposase affect the formation and dissolution of (IS30)2 dimer

The transposase of IS30 catalyses different transpositional rearrangements via the dimer (IS30)2 intermediate structure. Mutation analysis provides evidence that the C-terminal part of IS30 transposase is required for the formation and dissolution of (IS30)2 dimer. C-terminal mutants are also defective in transpositional fusion; however, this deficiency can be 'suppressed' by addition of the final product of site-specific dimerisation, the core (IS30)2 intermediate structure. The transposase part studied shows significant homologies in three highly conserved regions to proteins of IS30-related mobile elements.