Plasmid refers to the separated DNA molecule from chromosomal DNA, which has the ability to replicate on its own.
Plasmids are known to be small, circular molecules of DNA that have the ability to replicate independently, as they do not depend on the organism’s chromosomal DNA for replication. Due to this, plasmids are also known as extrachromosomal DNA. Plasmids are vital tools in genetic engineering as they help in gene cloning and gene therapy.
Plasmids are found in bacterial cells and certain eukaryotes. A plasmid measures up to 1 to 200 kb in size and produces enzymes that can degrade antibiotics or heavy metals. Plasmids have several functions like plasmids have genes that improve the survival of the organism, either by releasing toxins to defend the host cell or by killing other organisms. There are five main types of plasmids namely, fertility F-plasmids, resistance plasmids, virulence plasmids, degradative plasmids and Col plasmids.
Frequently Asked Questions on Plasmid Definition
Plasmids are defined as small, circular molecules of DNA that have the ability to replicate on their own.
Who discovered plasmids?
Plasmids were discovered in 1952, and the word was coined by Joshua Lederberg.
- R-Factor – Structure and Functions of Resistance Factors or Plasmids
- Do All Bacteria Have Plasmids?- An Overview of Plasmids and its Functions
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