What is pGEX plasmid?

What is pGEX plasmid?

Plasmid: pGEX-1 Expression vector permitting production of a fusion protein. (ATCC staff) The glutathione S-transferase (GST) fusion protein can be purified by glutathione affinity chromatography, and the desired polypeptide released from the fusion product by thrombin.

What is pGEX?

pGEX-2TK is designed to allow the detection of expressed proteins by directly labeling the tagged products in vitro. This vector contains the recognition sequence for the catalytic subunit of cAMP-dependent protein kinase obtained from heart muscle.

How does tac promoter work?

The tac promoter is used to control and increase the expression levels of a target gene and is used in the over-expression of recombinant proteins. The tac promoter is named after the two promoters which comprise its sequence: the ‘trp’ and the ‘lac’ promoters.

What are pGEX vectors?

pGEX vectors are widely used for GST-fusion protein expression in Escherichia coli under the control of a strong IPTG inducible tac promoter. While using pGEX-4T-2 vector in heterologous protein expression we noticed that the GST or GST-fusion protein were expressed at a very low levels.

What is the sequence of lac promoter?

The lactose (lac) operon promoter is positively regulated by the catabolite gene activator-cyclic AMP complex (CAP) that binds to the DNA located 61.5 bp upstream of the transcription start site. Between the CAP binding site and the core promoter sequence is a 13-bp sequence (from -38 to -50 [the -45 region]).

What is MCS in recombinant DNA?

A multiple cloning site (MCS), also called a polylinker, is a short segment of DNA which contains many (up to ~20) restriction sites – a standard feature of engineered plasmids. Restriction sites within an MCS are typically unique, occurring only once within a given plasmid.

What is the T3 promoter?

T3 Promoter. 5′ AATTAACCCTCACTAAAG 3′ T3 RNA polymerase starts transcription at the underlined G in the promoter sequence. The polymerase then transcribes using the opposite strand as a template from 5´→3´.

Why is the lac promoter weak?

Promoter of lac repressor gene is weak. P of lac repressor = P for the R gene; controls production of mRNA for lac repressor → lac repressor protein. Since this P is weak, you make only a little of the mRNA, and relatively little of the repressor protein.

How long is the lacZ gene?

3075 base pairs
LacZ gene size

What is pgex-4t-1 used for?

pGEX-4T-1. Bacterial vector for expressing fusion proteins with a thrombin site. For other reading frames, use pGEX‑4T-2 or pGEX‑4T-3. To see this sequence with restriction sites, features, and translations, please download SnapGene or the free SnapGene Viewer.

Is the pgex-1 lambda vector available from Addgene?

This vector is NOT available from Addgene. thrombin or factor Xa protease sites to cleave protein from fusion. pGEX-1lambdaT, pGEX-4T-1, pGEX-5X-1 accept cDNA from lambda gt11 libs. Hosts: E.coli. Related vectors: pGEX-2T.

Which vector should I use to express fusion proteins?

Bacterial vector for expressing fusion proteins with a thrombin site. For other reading frames, use pGEX-4T-1 or pGEX-4T-2. Sticky ends from different BtgI sites may not be compatible.

What is the difference between pgex-2tk and other vector types?

Protease cleavage sites of pGEX vectors pGEX-2TK has a different MCS from that of the other vectors. pGEX-2TK is designed to allow the detection of expressed proteins by directly labeling the tagged products in vitro. This vector contains the recognition sequence for the catalytic subunit of cAMP-dependent protein kinase obtained from heart muscle.