These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: DNA probe assay based on exonuclease III digestion of probes hybridized on target DNA.
    Author: Okano K, Kambara H.
    Journal: Anal Biochem; 1995 Jun 10; 228(1):101-8. PubMed ID: 8572265.
    Abstract:
    A quantitative DNA probe assay process has been developed that uses exonuclease III. The fluorophore-labeled DNA probe is hybridized with specific sequences of the target DNA and then enzymatically digested. As these probe hybridization and digestion cycle reactions are repeated at a fixed temperature, digested probes (shortened probes) accumulate in the reaction mixture in a manner similar to a DNA polymerase chain reaction. Investigation of the digestion characteristics of the DNA probe showed that a slight digestion of a free single-stranded probe produces a large background signal, which results in low detection sensitivity. The digestion of single-stranded DNA probes is caused by double-stranded formations in the molecules. This digestion decreases and the double-stranded-specific digestion increases with increasing reaction temperature. When the reaction occurs at 45 degrees C, the association rate of the enzyme on the double-stranded DNA is 700 times faster than that on single-stranded DNA. This enables selective digestion of double-stranded DNA. The detection limit is 9 x 10(-19) mol for a M13-phage DNA.
    [Abstract] [Full Text] [Related] [New Search]