biotechnology Flashcards
restriction enzymes
used to remove a target gene from one organism and inserting into the genome of a suitable host
where does restriction enzymes cut
at specific locations called restriction sites
types of cuts from restriction enzymes
restriction enzymes cut straight across the enzyme and create blunt ends with no exposed based, other cut in an offset way to create sticky ends with exposed bases
results of the restriction enzyme cutting
restriction fragments are made in varying lengths
what is done with restriction fragments after
immersed in a solution with gene probes
gene probes properties
single stranded (DNA or RNA), has complementary nucleotide sequence to target gene, and is radioactive/flourescently marked to indicated the gene is bound to the target gene
recombinant DNA
uses a vector (plasmid) to insert target gene into the genome of the host
common vector utilised
plasmids
process of recombinant DNA being formed
plasmid isolated from original host bacteria, cut by the SAME restriction enzyme used to remove the target gene, restriction enzyme leaves sticky ends on both plasmid and target gene, allowing target gene to form hydrogen bonds with complementary bases on the plasmid
what does ligase do
join the target gene to the plasmid forming recombinant DNA
bacterial plasmids
contain genes that have resistance to some antibotics, insertion of the target gene will be added into one of these resistance genes
bacterial transformation
recombinant DNA mixed with the cells of a host
common hosts of bacterial transformation
bacteria or yeast
how bacterial transformation occurs
through electroporation where the host cell is shocked with electrical energy to form holes in the cell membrane where the plasmid DNA can enter the cell
What is bacteria containing target gene called
transcribed, where they are cultured and grown
why are viruses used as vectors sometimes
as they are able to transfer genetic material to host
how viruses transfer target gene to host
the target gene is inserted into the viral genome, the virus is used to infect the host cells genome with the target gene
Transgenic plants
genes are located and inserted into a bacteria plasmid using gene probes and restriction enzymes. The DNA from the plasmid is inserted into the plant cell where it inserts itself into the plant chromosome.
types of vectors
uses microinjection, plasmids and viruses
CRISPR
Clustered Regularly Interspaced Short Palindromic Repeats
where did CRISPR originate from
bacteria used in defence against viruses
Cas 9 (CRISPR associated protein 9)
the guide RNA is loaded onto cas 9, which is able to cut DNA at a specific site corresponding to the target DNA, destroying the target DNA
gRNA
guide RNA has nucleotide sequence complementary to the target DNA and bonds with the target DNA helps cas 9 to locate the target DNA
CRISPR/cas9 use in biotechnology
gene editing (switching genes off and on), editing faulty genes (potential to cure cancer)
benifits of CRISPR
quickly edited, inexpensive, specific and accurate
limitations of CRISPR
cuts made by cas 9 can be repaired before gene is inserted, unwanted cuts if target nucleotide sequence occurs more than once
