What is a T7 promoter?
The T7 promoter is a sequence of DNA 18 base pairs long up to transcription start site at +1 (5′ – TAATACGACTCACTATAG – 3′) that is recognized by T7 RNA polymerase1 .
Where does T7 promoter come from?
T7 RNAP is a small (99 kDa) DNA-dependent RNAP derived from bacteriophage T7 (Chamberlin and Ring, 1973; Golomb and Chamberlin, 1974; Steitz, 2004). The polymerase efficiently and specifically transcribes genes bearing a T7 promoter (PT7).
Is T7 a strong promoter?
T7 RNA polymerase is very selective and efficient, resulting both in a high frequency of transcription initiation and effective elongation. coli RNA polymerase; hence, the T7 promoter is a much stronger promoter than the E.
How does the T7 expression system work?
T7 expression hosts such as DE3 prophage strains or T7 Express strains carry a chromosomal copy of the phage T7 RNA polymerase gene. When inducer is added, T7 RNA polymerase is expressed and becomes dedicated to target gene transcription.
What’s a terminator sequence?
A sequence in DNA that signals termination of transcription to RNA Polymerase. This should not be confused with terminator codons that are the stopping signal for translation. Also known as: terminator, rho-independent termination site.
What is rrnB T1 terminator?
The termination region of the rrnB gene coding for ribosomal RNA in Escherichia coli is large and complex. It contains two regions (T1 and T2) with typical factor-independent terminator-like sequences, two additional inverted repeats (lR1 and IR2) and a pair of direct repeats.
What is T7 epitope tag?
T7 Epitope Tag Products The T7 tag is an 11 amino acid peptide encoded in the leader sequence of T7 bacteriophage gene10. The T7 tag serves as a tag in many expression vectors including the pET system that is based on the very efficient T7 RNA polymerase expression system.
What is T7 protein expression?
The T7 expression system allows high-level expression from the strong bacteriophage T7 promoter. It’s ideal for expressing soluble, nontoxic recombinant proteins in E. coli. The T7 expression vectors are designed to facilitate cloning using Gateway® technology, and easy protein purification and detection.
What is a rut sequence?
Rho utilisation site, also known by the acronym rut, is a sequence of RNA in bacteria upstream of the terminator region which serves as a binding site for the protein known as rho factor. This sequence is necessary in rho-dependent termination of DNA transcription in bacteria.