Construction of new vectors for cloning of promoters |
| |
Authors: | B E Enger-Valk J van Rotterdam A Kos P H Pouwels |
| |
Institution: | Medical Biological Laboratory TNO, P.O. Box 45, 2280 AA Rijswijk The Netherlands |
| |
Abstract: | Vectors for cloning promoter-DNA fragments were derived from plasmid pBR313 (Bolivar et al., 1977). These have several unique restriction sites and carry the trpA gene from Escherichia coli as a selective marker. The selection is based on an enhancement of the growth rate of those bacteria in which the expression of trpA is directed by the cloned promoter. The expression of trpA can be determined quantitatively, independently of the copy number of the vector, and should reflect the apparent strength of the promoter, since the DNA segment located before trpA contains translational stop signals in all three reading frames. |
| |
Keywords: | Plasmids tryptophan gene bp base pairs kb kilobase pairs TSase A tryptophan synthetase |
本文献已被 ScienceDirect 等数据库收录! |