Recombinant DNA And Biotechnology Flashcards
The discovery of what enzymes paved the way for the development of recombinant DNA technologies?
Restriction enzymes also known as restriction endonucleases
These restriction enzymes occur in prokaryotes and Arachaea, where they act as a defense system against invading viruses by cleaving DNA in response to specific __________ _____, corresponding to sequences of 4-8 bases
Recognition sites
These recognition sites are usually involved in some degree of symmetry
Palindromic sequences
5’—>3’ sequences are the same for each strand
Blunt ends vs sticky ends
Blunt- Cleaves DNA sequence vertically (ex. Smal)
Sticky- Cleaves DNA in a zigzag fashion (ex. EcoRI)
Restriction enzymes are important because they can generate fragments that can be “tied” back together by ______ ______ without respecting the original location of the sequences
DNA ligase
The process in which sequences of DNA from two different species can be combined when digested with the same restriction enzyme then use DNA ligase to tie back together.
Recombination
These are DNA molecules used too carry genetic material into a cell where it can be replicated or expressed to make large quantities of those DNA sequences.
Vectors
Two types of vectors
Plasmids and bacteriophages
Short circular DNA molecules that can replicate independently in bacteria
Plasmids
*Recombinant plasmids carrying human DNA inserts can be introduced into E.coli, where they replicate along with the bacteria to yield millions of copies of plasmid DNA
Antibiotic resistance
Kill e.coli cells that did not take up the plasmid by adding antibiotic in the culture
To distinguish between the non-recombinant and recombinant plasmids, we use a
Reporter gene- express a phenotypic change such as a change in color when it is a recombinant DNA
Diagram of plasmid
Biology book, pg. 114
A feature of the plasmid that tells host cell DNA polymerase to initiate replication
Origin of replication
Feature of plasmid: recognition sit for a restriction enzyme to cleave DNA
Restriction site
Feature of plasmid that allows selection of bacteria that have taken up the plasmid
Antibiotic resistance gene
Feature of plasmid that distinguishes bacteria with recombinant plasmids from those with non-recombinant plasmids
Reporter gene
Limitation of plasmids?
Size- can only generally contain 2-4 kb of DNA
Bacteriophage lambda vectors vs Bacteriophage P1 vector
Bacteriophage lambda- can only do up to 15kb
P1- can do more than that
Major difference between plasmid vectors and bacteriophage vectors?
Bacteriophage vectors work by stripping out non-essential genes to carry recombinant sequences
RNA can also be cloned, through the generation of?
Complementary DNA (cDNA)- complementary to the template RNA cDNA can be lighted to vector DNA
Term that refers to any organism whose genome has been modified, for practical purposes or elucidate the function of genes
Transgenic
Those in which one or more genes have been disabled. The goal of such research is to compadre the functionality of organisms without a functioning copy of a given gene with wild-type organisms, in order to obtain more information about the function of the gene
Knockout organisms
An ongoing research that found theoretically allow the effective treatment of devastating genetic disorders. The idea is to splice in a functional copy of a gene in the cells of a patient with a nonfunctional allele.
Gene therapy
DNA technology in pharmacology
Many substances crucial for medial treatment are now produced by recombinant bacteria, such as insulin, tumors necrosis factor, interferons. And components of vaccines.
