Pcr

موضوع: Pcr الثلاثاء يناير 12, 2010 2:51 pm

The polymerase chain reaction PCR

It is a procedure for amplifying DNA in vitro.

Purpose: multiplication/ copy DNA to many copies.

Materials:
• DNA fragment
• DNA polymerase ( Taq or Pfy )
• Primer ( forward & reverse primer)
• Nucleotides(d NTP )

Steps:
1- denaturation step:
At 95c ,To get single strands of DNA
2-annealing step:
To anneal primer to the single strand of DNA, annealing temperature varies depending on primer , but normally it ranges (40-60c)
3-Extension step:
Copping of the two DNA strands at 72c.

• Both Taq & Pfy polymerase are heat-stable, but Pfy has proofreading activity.

PCR applications:
• comparative & phylogenetic studies.
• Amplify very small quantities of DNA.
• Diagnostic microbiology
• DNA fingerprinting as a forensic tool.

موضوع: رد: Pcr الأربعاء مارس 09, 2011 1:05 am

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