Guanidinium thiocyanate
Encyclopedia
Guanidinium thiocyanate (GITC) is a chemical compound
used as a general protein denaturant, being a chaotropic agent
, although it is most commonly used in the extraction of DNA and RNA.
Note: this compound may also be recognized as guanidine thiocyanate. This is because guanidinium is the conjugate acid of guanidine
and is called the guanidinium cation, [CH6N3]+.
Guanidinium thiocyanate can be used to deactivate a virus
, such as the influenza virus
that caused the 1918 "Spanish flu
" so that it can be studied safely. This application is presumably based on its denaturation activity.
Guanidinium thiocyanate is also used to lyse
cells and virus particles in RNA and DNA extractions, where its function, in addition to its lysing action, is to prevent activity of RNase enzymes and DNase enzymes by denaturing them. These enzymes would otherwise damage the extract.
A commonly used method is Guanidinium thiocyanate-phenol-chloroform extraction. It is not strictly necessary to use phenol or chloroform if extracting RNA for Northern blot
ting or DNA for Southern blot analysis because the gel electrophoresis followed by transfer to a membrane will separate the RNA/DNA from the proteins. Additionally, since these methods use probes to bind to their conjugates, peptides that get through the process don't generally matter unless a peptide is an RNase or DNase, and then only if the enzyme manages to renature, which should not occur if proper protocols are followed. A possible exception might be when working with temperature extremophiles because some enzymes of these organisms can remain stable under extraordinary circumstances.
Chemical compound
A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...
used as a general protein denaturant, being a chaotropic agent
Chaotropic agent
A denaturating agent is a substance which disrupts the three dimensional structure in macromolecules such as proteins, DNA, or RNA and denatures them. A denaturating agent is a chaotropic agent, but chaotropic agents aren't necessarily denaturating agents...
, although it is most commonly used in the extraction of DNA and RNA.
Note: this compound may also be recognized as guanidine thiocyanate. This is because guanidinium is the conjugate acid of guanidine
Guanidine
Guanidine is a crystalline compound of strong alkalinity formed by the oxidation of guanine. It is used in the manufacture of plastics and explosives. It is found in urine as a normal product of protein metabolism. The molecule was first synthesized in 1861 by the oxidative degradation of an...
and is called the guanidinium cation, [CH6N3]+.
Guanidinium thiocyanate can be used to deactivate a virus
Virus
A virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea...
, such as the influenza virus
Influenza
Influenza, commonly referred to as the flu, is an infectious disease caused by RNA viruses of the family Orthomyxoviridae , that affects birds and mammals...
that caused the 1918 "Spanish flu
Spanish flu
The 1918 flu pandemic was an influenza pandemic, and the first of the two pandemics involving H1N1 influenza virus . It was an unusually severe and deadly pandemic that spread across the world. Historical and epidemiological data are inadequate to identify the geographic origin...
" so that it can be studied safely. This application is presumably based on its denaturation activity.
Guanidinium thiocyanate is also used to lyse
Lysis
Lysis refers to the breaking down of a cell, often by viral, enzymic, or osmotic mechanisms that compromise its integrity. A fluid containing the contents of lysed cells is called a "lysate"....
cells and virus particles in RNA and DNA extractions, where its function, in addition to its lysing action, is to prevent activity of RNase enzymes and DNase enzymes by denaturing them. These enzymes would otherwise damage the extract.
A commonly used method is Guanidinium thiocyanate-phenol-chloroform extraction. It is not strictly necessary to use phenol or chloroform if extracting RNA for Northern blot
Northern blot
The northern blot is a technique used in molecular biology research to study gene expression by detection of RNA in a sample. With northern blotting it is possible to observe cellular control over structure and function by determining the particular gene expression levels during differentiation,...
ting or DNA for Southern blot analysis because the gel electrophoresis followed by transfer to a membrane will separate the RNA/DNA from the proteins. Additionally, since these methods use probes to bind to their conjugates, peptides that get through the process don't generally matter unless a peptide is an RNase or DNase, and then only if the enzyme manages to renature, which should not occur if proper protocols are followed. A possible exception might be when working with temperature extremophiles because some enzymes of these organisms can remain stable under extraordinary circumstances.