2.7 Genetic Control of Metabolism Flashcards
wild strains of microorganisms can be improved by… (2)
- mutagenesis
- recombinant DNA technology
mutations can result from… (3)
- UV light
- radiation
- mutagenic chemicals
mutations can have a … or … effect
positive or negative
what does recombinant DNA technology involve the use of?
recombinant plasmids and artificial chromosomes as vectors
vector
a DNA molecule used to carry foreign genetic information into another cell
when are artificial chromosomes preferable to recombinant plasmids as vectors?
when larger fragments of DNA have to be inserted
what 2 enzymes are required for the manipulation of DNA?
- ligase
- restriction endonuclease
role of restriction endonuclease in recombinant DNA technology
cuts open plasmids or cuts specific genes out of chromosomes, and leaves behind sticky ends
role of ligase in recombinant DNA technology
seals the desired gene into the plasmid
features of recombinant plasmids and artificial chromosomes (3)
- restriction sites
- regulatory sequences
- selectable markers
restriction sites
contains target sequences of DNA, where specific restriction endonucleases cut
regulatory sequences
control gene expression, and is the origin of replication which allows self replication
selectable markers
- protect from selective agents that might kill it or prevent growth
- ensure that only microorganisms which have taken up the vector grow in the presence of the selective agent
safety mechanism
genes are often introduced that prevent the survival of the microorganism in an external environment
recombinant yeast cells
used to produce correctly folded, active forms of proteins taken from other cells which would otherwise be inactive in bacteria
