Nucleic acid binding polypeptides characterized by flexible linkers connected nucleic acid binding modules

We describe a method of producing a modified nucleic acid binding polypeptide, the method comprising the steps of: (a) providing a nucleic acid binding polypeptide comprising a plurality of nucleic acid binding modules; (b) selecting a first binding domain consisting of one or two contiguous nucleic acid binding modules; (c) selecting a second binding domain consisting of one or two contiguous nucleic acid binding modules; and (d) introducing a flexible linker sequence to link the first and second binding domains, the flexible linker sequence comprising five or more amino acid residues. Use of structured linkers, alone or in combination with flexible linkers, is also disclosed.