The transformed cells then can be selected from the untransformed cells by inclusion of an antibiotic to kill off the untransformed cells. Typically, this occurs as the plasmid will express an antibiotic resistance gene to protect the transformed cells and ensure maintenance of the plasmid over time and cell divisions. In the process, many replicons of the plasmid will be created and passed to daughter cells.
Transfection is a type of plasmid transformation, typically that of animal cells, instead of bacteria. This process is a bit more complicated than your run-of-the-mill transformation, as many lab-cultured eukaryotic cells do not natively uptake and replicate foreign DNA. Still, scientists have discovered many ways in which plasmids and other foreign DNA can be introduced to cells. Much like methods for bacteria, there are both chemical and physical methods of transfection produce transient holes in the cell membrane and get uptake of foreign DNA.
These methods work similarly to the those outlined for bacterial transformation, as they all are designed to make the cell membrane more permeable. You have authorized LearnCasting of your reading list in Scitable. Do you want to LearnCast this session? This article has been posted to your Facebook page via Scitable LearnCast. Change LearnCast Settings. To do this scientists commonly use phagemids , a DNA cloning vector that contains both bacteriophage and plasmid properties. Scientists also use transduction to introduce foreign DNA into eukaryotic cells, like mammalian cell lines.
You can find all kinds of different lentiviral and AAV plasmids as well as ready-to-use viral preparations at Addgene. For more information on viral vectors, including transduction download our Viral Vectors eBook.
Conjugation was the first extensively studied method of gene transfer and was discovered in by Joshua Lederberg and Edward Tatum when they observed genetic recombination between two nutritional deficient E.
During conjugation, genetic material is transferred from a donor bacterium to a recipient bacterium through direct contact. Once in contact the donor can transfer genetic material to the recipient bacterium. The genetic material transferred is commonly a plasmid and can infer genetic advantages such as antibiotic resistance.
Unlike the last three methods which can be used in prokaryotes, transfection is only done in eukaryotic cells. Transfection is the process by which foreign DNA is deliberately introduced into a eukaryotic cell through non-viral methods including both chemical and physical methods in the lab.
Chemicals like calcium phosphate and diethylaminoehtyl DEAE -dextra neutralize or even impart an overall positive charge on DNA molecules so that it can more easily cross the negatively charged cell membrane. Physical methods such as electroporation or microinjection actually pokes holes in the cell membrane so DNA can be introduced directly into the cell. In transduction, bacteriophage inserts DNA fragment into bacteria. Hence this is a significant difference between transformation and transduction.
Additionally, a further difference between transformation and transduction is that a plasmid transfer is possible in transformation while it is not likely to occur in transduction.
Above these, another significant difference between transformation and transduction is that the transformation is susceptible to DNAase while transduction is DNAase resistant. Below infographic presents the difference between transformation and transduction as a side by side comparison. Transformation and transduction are two ways of horizontal gene transferring among bacteria. Transformation is the process of direct uptake of exogenous DNA from the surrounding via cell wall and membrane into the bacterial cell and incorporation to its genome.
On the other hand, transduction is the process of injecting viral DNA into bacterial cells by the bacteriophages. Hence, transduction is done by a viral host. Furthermore, transformation occurs naturally and artificially. It depends on the competence of the bacteria. Transduction does not depend on the competence of the bacteria. Transduction occurs via lytic and lysogenic cycle.
Thus, this is the difference between transformation and transduction.
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