Restriction digests of the clone give the following sizes (kb): EcoRI--5.8; BamHI--5.8; PstI--5.8. This strain is resistant to 100 ug/ml ampicillin. The recombinant fusion protein generated using this vector is not solubilized in Triton X-100 lysis procedures and is thus easily purified, resistant to proteolysis, and easily detected by direct immunoscreening. This is one of three bacterial expression vectors (pEX11, ATCC 37708; pEX12, ATCC 37709; and pEX13, ATCC 37710) which differ by translational reading frames and which express cro-lacZ fusion proteins regulated by the PR promoter of bacteriophage lambda. This was constructed from pEX3 by ligating a synthetic oligonucleotide into pEX3 cut with XmaI and BamHI. The oligonucleotide added several unique restriction sites. |
