pulsed-field gel electrophoresis
{{short description|Lab technique for separation of DNA}}
Pulsed-field gel electrophoresis (PFGE) is a technique used for the separation of large DNA molecules by applying an electric field that periodically changes direction to a gel matrix.{{cite book |doi=10.1385/0-89603-498-4:33 |chapter=Pulsed-Field Gel Electrophoresis |title=Molecular Bacteriology |year=1998 |last1=Kaufmann |first1=Mary Elizabeth |series=Methods in Molecular Medicine |volume=15 |pages=33–50 |pmid=21390741 |isbn=0-89603-498-4 }}{{cite journal |last1=Herschleb |first1=Jill |last2=Ananiev |first2=Gene |last3=Schwartz |first3=David C |title=Pulsed-field gel electrophoresis |journal=Nature Protocols |date=March 2007 |volume=2 |issue=3 |pages=677–684 |doi=10.1038/nprot.2007.94 |pmid=17406630 |s2cid=13265518 }} Unlike standard agarose gel electrophoresis, which can separate DNA fragments of up to 50 kb, PFGE resolves fragments up to 10 Mb. This allows for the direct analysis of genomic DNA.
History
In 1984, David C. Schwartz and Charles Cantor published the first successful application of alternating electric fields for the separation of large DNA molecules.{{cite journal |last1=Lopez-Canovas |first1=Lilia |last2=Martinez Benitez |first2=Maximo B. |last3=Herrera Isidron |first3=Jose A. |last4=Flores Soto |first4=Eduardo |title=Pulsed Field Gel Electrophoresis: Past, present, and future |journal=Analytical Biochemistry |date=May 2019 |volume=573 |pages=17–29 |doi=10.1016/j.ab.2019.02.020}}{{Cite journal |last1=Schwartz |first1=David C. |last2=Cantor |first2=Charles R. |title=Separation of yeast chromosome-sized DNAs by pulsed field gradient gel electrophoresis |url=https://linkinghub.elsevier.com/retrieve/pii/0092867484903015 |journal=Cell |year=1984 |language=en |volume=37 |issue=1 |pages=67–75 |doi=10.1016/0092-8674(84)90301-5|pmid=6373014 |s2cid=30743288 }} This technique, which they named PFGE, resulted in the development of several variations, including Orthogonal Field Alternation Gel Electrophoresis (OFAGE), Transverse Alternating Field Electrophoresis (TAFE), Field-Inversion Gel Electrophoresis (FIGE), and Clamped Homogeneous Electric Fields (CHEF), among others.
Procedure
File:E. coli cluster analysis-pulsed-field gel electrophoresis.jpg of the enteroaggregative Escherichia coli strains from the pulsed-field gel electrophoresis fingerprinting]]
The procedure for PFGE is similar to that of standard agarose gel electrophoresis, with the main exception being the application of the electric current. Generally, in PFGE electrophoresis chambers, the voltage periodically switches between three directions: one along the central axis, and two at a 60 degree angle along each side.{{cite web |title=What is Pulsed Field Gel Electrophoresis? |url=https://www.neb.com/en-us/tools-and-resources/video-library/what-is-pulsed-field-gel-electrophoresis |website=New England Biolabs |access-date=1 July 2024}} The application of the voltage can change depending on the variation of PFGE used.{{cite journal |last1=Nassonova |first1=E. S. |title=Pulsed field gel electrophoresis: Theory, instruments and application |journal=Cell and Tissue Biology |date=1 December 2008 |volume=2 |issue=6 |pages=557–565 |doi=10.1134/S1990519X08060011 |url=https://link.springer.com/article/10.1134/S1990519X08060011 |language=en |issn=1990-5203}}{{cite journal |last1=Goering |first1=Richard V. |title=Pulsed field gel electrophoresis: A review of application and interpretation in the molecular epidemiology of infectious disease |journal=Infection, Genetics and Evolution |date=October 2010 |volume=10 |issue=7 |pages=866–875 |doi=10.1016/j.meegid.2010.07.023}}
Applications
PFGE may be used for genotyping or genetic fingerprinting. It has commonly been considered a gold standard in epidemiological studies of pathogenic organisms for several decades. For instance, subtyping bacterial isolates with this method has made it easier to discriminate among strains of Listeria monocytogenes, Lactococcus garvieae{{cite journal |last1=Rao |first1=Shreesha |last2=Chen |first2=Mei-Yun |last3=Sudpraseart |first3=Chiranan |last4=Lin |first4=Peiry |last5=Yoshida |first5=Terutoyo |last6=Wang |first6=Pei-Chi |last7=Chen |first7=Shih-Chu |title=Genotyping and phenotyping of Lactococcus garvieae isolates from fish by pulse-field gel electrophoresis (PFGE) and electron microscopy indicate geographical and capsular variations |journal=Journal of Fish Diseases |date=June 2022 |volume=45 |issue=6 |pages=771–781 |doi=10.1111/jfd.13601|pmid=35235703 }} and some clinical isolates of Bacillus cereus {{cite journal |last1=Cheng |first1=Li-Wu |last2=Rao |first2=Shreesha |last3=Poudyal |first3=Sayuj |last4=Wang |first4=Pei-Chi |last5=Chen |first5=Shih-Chu |title=Genotype and virulence gene analyses of Bacillus cereus group clinical isolates from the Chinese softshell turtle (Pelodiscus sinensis) in Taiwan |journal=Journal of Fish Diseases |date=October 2021 |volume=44 |issue=10 |pages=1515–1529 |doi=10.1111/jfd.13473}} group isolated from diseases aquatic organisms and thus to link environmental or food isolates with clinical infections. It is now in the process of being superseded by next generation sequencing methods.{{cite journal |last1=Ribot |first1=Efrain M. |last2=Freeman |first2=Molly |last3=Hise |first3=Kelley B. |last4=Gerner-Smidt |first4=Peter |title=PulseNet: Entering the Age of Next-Generation Sequencing |journal=Foodborne Pathogens and Disease |date=July 2019 |volume=16 |issue=7 |pages=451–456 |doi=10.1089/fpd.2019.2634 |pmid=31241352 |pmc=6653803 }}
See also
References
{{reflist}}
External links
- [http://www.bio.davidson.edu/courses/genomics/method/pulse_field.html Pulse field method]
- [http://www.applied-maths.com/applications/pulsed-field-gel-electrophoresis-pfge-typing Applied Maths] BioNumerics PFGE typing
{{Electrophoresis}}
{{DEFAULTSORT:Pulsed Field Gel Electrophoresis}}