how can a biology used plasmids to produce bacteria that carry a specific gene?

Answer 1

First, a scientist must locate the specific gene, which can be extremely hard to find among the large genomes of complex organisms like humans. Then the specifc gene must somehow be isolated. A common method of gene isolation is the use of restriction endonucleases (restriction enzymes). These enzymes are used to cut DNA into fragments until the needed gene is isolated. Other restriction enzymes are then used to cut open a bacterial plasmid, which will basically be used as a cloning vector. A plasmid is a small, circular self-replicating DNA molecule found in bacterial cells. The DNA fragment is inserted into the plasmid, and is able to seemlessly become part of the plasmid with the help of DNA ligases. The genetically altered plasmid is reinserted into a bacterial cell. Now, when the bacterial cell divides, the daughter cells will inherit the recombinant DNA from the genetically altered plasmid. The cells will then move on to translate the recombinant DNA into the proper protein products. Since bacteria divide so rapidly, many copies of the specific gene will be made. As you can see, bacteria can be induced to produce eukaryotic genes. A much better, more efficient way of mass-producing specific genes is using yeast as cloning vectors. The recombinant vectors called yeast artificial chromosomes (YACs) can carry more DNA than plasmids, enabling longer gene sequences to be replicated. Another advantage for using these eukaryotic yeast vectors is that you can avoid occasional prokaryotic/eukaryotic incompatibility. Also, another advantage of using yeast is that, being eukaryotic host cells, they have the ability to modify eukaryotic gene products after translation; prokaryotes can't do this.

* I know you didn't ask for all that information about yeast vectors, but I thought I might as well tell you in case you needed to know it, but forgot to ask. I am guessing that you're in a high school AP Biology class, but I may be wrong. I was in AP Biology in high school last year, and I definitely needed to know about this stuff.

Answer 2

done by recombinant dna technology restrict the plasmid and the target sequence at specific site using restriction enzymeand then ligate with dna ligase enzyme