Nicking enzyme amplification reaction
Encyclopedia
Nicking Enzyme Amplification Reaction (NEAR) is a method for in vitro
DNA
amplification like the polymerase chain reaction
(PCR). NEAR is isothermal, replicating DNA at a constant temperature using a polymerase
(and nicking enzyme
) to exponentially amplify the DNA at a temperature range of 55 °C to 59 °C.
The disadvantage of PCR is that it consumes a lot of time with uncoiling the double-stranded DNA with heat into single strands (a process called denaturation
) and copying the single strands to create new double-stranded DNA (synthesis
). This leads to amplification times typically thirty minutes or more for significant production of amplified products.
The advantages of NEAR over PCR are increased speed, reduced costs, lower energy requirements and the ability to perform the reaction in the field. The disadvantage of NEAR to PCR is that background production is a common issue with reactions due to the infancy of the technology.
In vitro
In vitro refers to studies in experimental biology that are conducted using components of an organism that have been isolated from their usual biological context in order to permit a more detailed or more convenient analysis than can be done with whole organisms. Colloquially, these experiments...
DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
amplification like the polymerase chain reaction
Polymerase chain reaction
The polymerase chain reaction is a scientific technique in molecular biology to amplify a single or a few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence....
(PCR). NEAR is isothermal, replicating DNA at a constant temperature using a polymerase
Polymerase
A polymerase is an enzyme whose central function is associated with polymers of nucleic acids such as RNA and DNA.The primary function of a polymerase is the polymerization of new DNA or RNA against an existing DNA or RNA template in the processes of replication and transcription...
(and nicking enzyme
Nicking enzyme
A nicking enzyme is an enzyme that cuts one strand of a double-stranded DNA at a specific recognition nucleotide sequences known as a restriction site. Such enzymes hydrolyse, cut, only one strand of the DNA duplex, to produce DNA molecules that are “nicked”, rather than cleaved...
) to exponentially amplify the DNA at a temperature range of 55 °C to 59 °C.
The disadvantage of PCR is that it consumes a lot of time with uncoiling the double-stranded DNA with heat into single strands (a process called denaturation
Denaturation (biochemistry)
Denaturation is a process in which proteins or nucleic acids lose their tertiary structure and secondary structure by application of some external stress or compound, such as a strong acid or base, a concentrated inorganic salt, an organic solvent , or heat...
) and copying the single strands to create new double-stranded DNA (synthesis
Biosynthesis
Biosynthesis is an enzyme-catalyzed process in cells of living organisms by which substrates are converted to more complex products. The biosynthesis process often consists of several enzymatic steps in which the product of one step is used as substrate in the following step...
). This leads to amplification times typically thirty minutes or more for significant production of amplified products.
The advantages of NEAR over PCR are increased speed, reduced costs, lower energy requirements and the ability to perform the reaction in the field. The disadvantage of NEAR to PCR is that background production is a common issue with reactions due to the infancy of the technology.