US Patent 7608434 Mutated Tn5 transposase proteins and the use thereof

Transposase proteins that are modified relative to and have higher transposase activities than the wild-type Tn5 transposase are disclosed. A transposase protein of the present invention differs from the wild-type Tn5 transposase at amino acid position 41, 42, 450, or 454 and has greater avidity than the wild-type Tn5 transposase for at least one of a Tn5 outside end sequence as defined by SEQ ID NO:3, a Tn5 inside end sequence as defined by SEQ ID NO:4, and a modified Tn5 outside end sequence as defined by SEQ ID NO:5. Also disclosed are various systems and methods of using the transposase proteins of the present invention for in vitro or in vivo transposition.