OVEREXPRESSION OF ESCHERICHIA-COLI SINGLE-STRANDED-DNA BINDING-PROTEIN UNDER BACTERIOPHAGE-T-7 PROMOTER

A recombinant vector for overproduction of the E. coil single stranded DNA binding protein (E. coli SSBP) has been constructed. An E. coli s train carrying this plasmid produces up to 15.0 mg pure SSBP per litre of bacterial culture in a laboratory shake flask. Electron microscopy of the single stranded DNA complexed with SSBP shows characteristic ' 'beaded string''-like appearance. Strong clustering of protein molecul es on ssDNA is indicative of a highly cooperative binding.