27 May 2011


Mutagenesis is a process by which the genetic information of an organism is changed in a stable manner, either in nature or experimentally by the use of chemicals or radiation. Mutagenesis as a science was developed especially by Charlotte Auerbach in the first half of the 20th century.

Insertional mutagenesis
Insertional mutagenesis is mutagenesis of DNA by the insertion of one or more bases.Insertional mutations can occur naturally, mediated by virus or transposon, or can be artificially created for research purposes in the lab.

Directed mutagenesis
Directed mutagenesis, also known as directed mutation, is a hypothesis proposing that organisms can respond to environmental stresses through directing mutations to certain genes or areas of the genome.

Transposon mutagenesis
Transposon mutagenesis, or transposition mutagenesis, is a biological process that allows genes to be transferred to a host organism's chromosome, interrupting or modifying the function of an extant gene on the chromosome and causing mutation.

PCR mutagenesis
PCR mutagenesis is a method for generating site-directed mutagenesis. This method can generate mutations (base substitutions, insertions, and deletions) from double-stranded plasmid without the need for subcloning into M13-based bacteriophage vectors and for ssDNA rescue. The procedure involves a PCR reaction using a supercoiled plasmid vector as the template and two synthetic oligonucleotide primers containing the desired mutation with each complementary to the opposite strands of the vector. After PCR, the template (wild type) plasmid which is dam methylated in almost all E. coli is removed by digestion with Dpn I which is specific for methylated DNA. The new (mutant) DNA is not methylated and remains intact in the reaction. The reaction products are then transformed into competent E. Coli, where the linear double-stranded PCR product is ligated by the host cell, and propagated by appropriate selection...

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