HomeProteinWhen Plasmids Are Used To Produce A Desired Protein
August 30, 2018
When Plasmids Are Used To Produce A Desired Protein
When Plasmids Are Used To Produce A Desired Protein – A plasmid is a small DNA molecule within a cell that is physically separated from a chromosomal DNA and can replicate independently. They are most commonly found as small circular, double-stranded DNA molecules in bacteria; however, plasmids are sometimes present in archaea and eukaryotic organisms.
When Plasmids Are Used To Produce A Desired Protein – While the chromosomes are big and contain all the essential genetic information for living under normal conditions, plasmids usually are very small and contain only additional genes that may be useful to the organism under certain situations or particular conditions.
When Plasmids Are Used To Produce A Desired Protein – When one wants to produce vast quantities of protein rapidly and cheaply, a bacterial host cell is almost always the answer. Protein expression in bacteria is quite simple; DNA coding for your protein of interest is inserted into a plasmid expression vector that is then transformed into a bacterial cell. Transformed cells propagate, are induced to produce your protein of interest, and then lysed. Protein can then be purified from the cellular debris.
What can plasmids be used for?
Plasmids can be used in a variety of ways to study the gene of interest. A few examples are described below:
Protein Function: Plasmids can be used to make the protein of interest in nearly any type of cell. If you are interested in studying whether a protein is involved in cancer, you may want to express it in human cells in culture and see if it makes the cells grow faster (a characteristic of cancer cells). You may already know the function of the protein, but you want to know precisely how it work, so you can change the DNA of the gene in the plasmid (by making a single mutation or removing whole pieces of the gene) and seeing how this affects it’s activity. If a mutation inactivates an enzyme, then you may have isolated the part of the protein that catalyzes the reaction.