Cloning of the resistant EcoRII recognition site of phage T7 into an EcoRII-sensitive plasmid makes the site susceptible to the restriction enzyme
✍ Scribed by Detlev H. Krüger; Susanna Prösch; Monika Reuter; Werner Goebel
- Publisher
- John Wiley and Sons
- Year
- 1990
- Tongue
- English
- Weight
- 363 KB
- Volume
- 30
- Category
- Article
- ISSN
- 0233-111X
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
The recognition sequence 5'‐CC(A/T)GG for __Eco__RII in the bacteriophage T7 genome is refractory to this restriction endonuclease, despite not bearing the specific (protective) methylation. Following the integration of this site as part of a 219 bp fragment (in which the recognition sequence is flanked by about 100 bp of T7 origin) into the __Eco__RII‐sensitive vector pUC18, the T7 site becomes susceptible to cleavage, too. The same is true of recombinant pBR322 plasmids containing the T7‐derived recognition site. The results show that the flanking sequences are not immediately responsible for the refractory behaviour of __Eco__RII sites and are in agreement with data according to which __Eco__RII requires the coordinated presence of at least two recognition sites in its DNA substrate.