Key Area 7: Gentic Control Of Metabolism Flashcards
How can wild strains of organisms be improved??
- mutagenesis
- selective breeding
- recombinant DNA technology
What is a wild type?
A wild type is the natural variety of a microbe
What is mutagenesis?
Inducing or encouraging mutations in an organism
How can mutagenesis be increased artificially?
Radiation or different chemicals
What does it mean if the new strain is genetically unstable?
They could return to their wild type at any time
How can bacteria produce new strains?
- horizontal gene transfer
- picking up genetic material from the environment
How can yeast and fungi produce new strains?
Sexual reproduction in breeding programmes
What is recombinant DNA technology?
The transfer of dna from one organism to another
What is the enzyme used in recombinant dna technology and what does it do?
Restriction endonucleas cuts dna at a specific sequence
What is the role of ligament enzymes in recombinant dna technology?
Join the sticky ends on the desirable gene and the plasmid
What is a vector?
A vector carries the dna from the original organism
What are two examples of a a vector?
- plasmids
- artificial chromosomes
What must a plasmid have to be a suitable vector?
- marker gene
- restriction site
- origin of replication
What is the function of the marker gene?
Resistant to antibiotics to help isolate only he bacteria that have been tranformed
What is the function of the restriction site?
Area that the plasmid is cut and the gene is inserted
What is the function of the origin of replication?
Allows new gene to be transcribed
What are two ways the existing strain can be improved?
- amplifying specific steps in a pathway or removing inhibitory controls to increase yield of a certain product
- as a safety mechanism the microbe can be made unable to survive in the external environment
Why is using prokaryotes restricted?
They only contain exons and lack post-translational modifications
How do scientists overcome the restriction of prokaryotes?
They produce desired human proteins using genetically transformed yeast (since yeast is a eukaryote)
