recombinant DNA technology

recombinant DNA technology
What is recombinant DNA?
Recombinant DNA is the formation of a novel DNA sequence by the formation of two DNA strands. These are taken from two different organisms. These recombinant DNA molecules can be made with recombinant DNA technology.
Wat is recombinant DNA technology?
The procedure is to cut the DNA of the donor organism into pieces with restriction enzymes, and insert one of these fragments into the DNA of the host. Most of the time a bacterial or virus plasmidis used to insert the donor DNA. A plasmid is a circular DNA fragment, which can be opened with the same restriction enzymes as the DNA fragment of the donor. A plasmid containing DNA from the donor is called a vector. The recombinant vector can then be used to transform bacterial or virus cells. These bacterial cells are plated and colonies are grown.
Antibiotic resistance
To only get the recombinant DNA containing bacteria, an antibiotic resistanceis built in the vector. The bacteria are then put on an anitbiotic containing plate. This means that only the vector containing bacteria will survive, because only they contain the antibiotic resistant gene.These grown colonies all contain the same recombinant vector in their genome. These population with all identical DNA inserts is called a DNA clone. When an entire genome is cut and grown in different colonies, you have a DNA library.
Recombinant eukaryotes
Dependant on the kind of bacteria you use, different experiments with the altered vectors are possible. First of all, it is possible to sequencethe inserted gene. In this way you can get the DNA sequence of a whole or a part of te genome. Another option is to use a bacterium which can infect other organismslike plants, animals or fungi. One of the examples of making recombinant plants, is the use of a bacterium called Agrobacterium tumefaciens. This bacterium can insert the vector, which contains the recombinant DNA, into a plant. In this way, a recombinant plant is made which can make the gene products of the inserted recombinant genes.
In the techniques written above all organisms and enzymes that are used come from nature themselve. All steps occur in nature themselve very regular. Only the insertation of eukaryotic genes into the plasmid of a bacteria is not seen yet in nature. But researchers expect that this is also a process which occurs in nature itself.