Flashcards in Intro genetic engineering - lecture 12 Deck (13)
What are restriction enzymes?
Cut phosphodiester bonds in DNA at specific sequences
Why do bacteria produce restriction enzymes?
To combat phage infection
EcoRv nuclease vs EcoRV methylase
EcoRv methylate is an enzyme which adds methyl groups to specific sequences , which prevents EcoRv nuclease form cutting there
catalyse the formation of phospodiester bonds between a 3' hydroxyl and a 5' phosphate group
What are DNA vectors?
Units that can be used to store, replicate and manipulate genetic info . Plasmids are commonly used.
What are expression vectors
Have a promoter near a multiple cloning site
How do you get a gene of interest into a plasmid/
- Restriction enzymes at end of gene
- Design PCR primer to have restriction enzymes at the end
what is the purpose of site directed mutagenesis?
Used to introduce specific changes within. the DNA sequence
How does site - directed mutagenesis occur?
- methylated template plasmid to start with
- Do PCR and you get a plasmid with no methylation
- Dnp1 restriction enzyme degrades methylated temple plasmid
- left with vector with mutation
The Cre- Loxp system
- Use of the Cyclization recombinase (cre) enzyme produced by bacteriophages
- Cre recognises Loxp sequences and induces a deleted sequence then recombination
What is Crispr - Casp?
- A cellular systems which exists in bacteria to combat viruses
- components have been humanised to edit human genomes
What does Palindromic mean?
n genetics, a DNA or RNA sequence that reads the same in both directions. The sites of many restriction enzymes that cut (restrict) DNA are palindromes.