METHOD FOR CLONING AND PRODUCTION OF AATII RESTRICTION ENDONUCLEASE AND METHYLASE AND METHOD FOR ASSOCIATION WITH EXCESSIVE EXPRESSION OF RESTRICTION ENDONUCLEASE

摘要

The present invention provides a novel approach to the production of restriction endonucleases. More specifically, there is provided a novel method for the overexpression of these enzymes, which comprises transforming a host cell with an expression vector containing DNA coding for the restriction endonuclease of interest and a vector for the expression of a methylase which is capable of protecting the host cell DNA against the restriction endonuclease of interest. The methylase vector is compatible with the restriction endonuclease expression vector. Preferably, the expression vector is a T7 expression vector and the cell is transformed with a third compatible vector which regulates the expression vector. The cloning and overexpression of the AatII restriction endonuclease and methylase is also described in detail.