Bioengineering, or genetic engineering is an altering of
genes in a particular species for a particular outcome.
It involves taking genes from their normal location in one
organism and either transferring them elsewhere or putting
them back into the original organism in different combinations.
Most biomolecules exist in low concentrations and as complex, mixed
populations which it is not possible to work efficiently. This problem
was solved in 1970 using a bug, Escherichia coli, a normally innocuous
commensal occupant of the human gut. By inserting a piece of DNA of interest
into a vector molecule, a molecule with a bacterial origin of replication, when
the whole recombinant construction is introduced into a bacterial colonies all
derived from a single original cell bearing the recombinant vector, in a short
time a large amount of DNA of interest is produced. This can be purified from
contaminating bacterial DNA easily and the resulting product is said to have been
"cloned".
So far, scientists have used genetic engineering to produce, for example:
? improve vaccines against animal diseases such as footrot and pig scours;
? pure human products such as insulin, and human growth hormone in commercial
quantities;
? existing antibiotics by more economical methods;
? new kinds of antibiotics not otherwise available;
? plants with resistance to some pesticides, insects and diseases;
? plants with improved nutritional qualities to enhance livestock productivity.
Methods:
? Manipulation of the Gene pool, which is related to Hybridization which is the breeding
of species but the species are not the same but they are related.
? Chain reaction is the production of many identical copies of a particular DNA
fragment.
? The utility of cloning is important, it provides the ability to determine the genetic
organization of particular regions or whole genome. However, it also facilitates the
production of naturally-occurring and artificially-modified biological products by the
expression of cloned genes.
? Insertion of selectable marker genes to pick out recombinant molecules containing
foreign inserts
? Removal or creation of useful sites for cloning
? Insertion of sequences which not only allow but greatly increase the expression of
cloned genes in bacterial, animal and plant cells.
? The ability to take a gene from one organism (e.g. man or tree), clone E. coli and
express it in another (e.g. a yeast) is dependent on the universality of the genetic
code, i.e. the triplets of bases which encode amino acids in proteins:
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