TE

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(Notes)
(Notes)
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==Notes==
==Notes==
*Use Tris base and adjust the pH to 8.0 using HCl.
*Use Tris base and adjust the pH to 8.0 using HCl.
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*TE buffer is often used to store DNA. The [[EDTA]] in TE chelates Mg<sup>2+</sup> ions necessary for most processes causing DNA degradation, and thus any residual DNA degradation activity will be suppressed by the presence of EDTA.  However, EDTA, for the same reason, also prevents restriction digests, PCR, and ligations.  So when using DNA that was suspended in TE you should keep track of the amount of EDTA in the mix to make sure there is still enough Mg<sup>2+</sup> for your reaction to proceed successfully. Each EDTA molecule chelates one Mg<sup>2+</sup> ion.
+
*TE buffer is often used to store DNA and RNA. The [[EDTA]] in TE chelates Mg<sup>2+</sup> and other divalent metals ions necessary for most causes of DNA and RNA degradation, suppressing these processes.  However, downstream reactions like restriction digests, PCR, ligations, and reverse transcription typically require Mg<sup>2+</sup>, potentially making the presence of EDTA in the reaction problematic.  So, when using DNA or RNA that was suspended in TE, you should keep track of the amount of EDTA in the mix to make sure there is still enough Mg<sup>2+</sup> for subsequent reactiosn to proceed successfully. Each EDTA molecule chelates one Mg<sup>2+</sup> ion.
*Some protocols use TE 10:0.1 with 0.1 mM EDTA to reduce the interaction of the EDTA with downstream applications.
*Some protocols use TE 10:0.1 with 0.1 mM EDTA to reduce the interaction of the EDTA with downstream applications.
 +
*Some people use TE buffers with different pH's for different applications. For example, DNA is stored at pH 8 to reduce depurination, which is acid catalyzed, while RNA is stored at a slightly lower pH (7.5) because degradation of RNA is base-catalyzed. Most downstream reactions will not be influenced by the slightly different pH storage conditions.

Revision as of 08:49, 17 April 2006

TE is 10 mM Tris-HCl, 1 mM EDTA

10X pH 8.0 Recipe

  • 100mM Tris-Cl (pH 8.0)
  • 10mM EDTA (pH 8.0)

Notes

  • Use Tris base and adjust the pH to 8.0 using HCl.
  • TE buffer is often used to store DNA and RNA. The EDTA in TE chelates Mg2+ and other divalent metals ions necessary for most causes of DNA and RNA degradation, suppressing these processes. However, downstream reactions like restriction digests, PCR, ligations, and reverse transcription typically require Mg2+, potentially making the presence of EDTA in the reaction problematic. So, when using DNA or RNA that was suspended in TE, you should keep track of the amount of EDTA in the mix to make sure there is still enough Mg2+ for subsequent reactiosn to proceed successfully. Each EDTA molecule chelates one Mg2+ ion.
  • Some protocols use TE 10:0.1 with 0.1 mM EDTA to reduce the interaction of the EDTA with downstream applications.
  • Some people use TE buffers with different pH's for different applications. For example, DNA is stored at pH 8 to reduce depurination, which is acid catalyzed, while RNA is stored at a slightly lower pH (7.5) because degradation of RNA is base-catalyzed. Most downstream reactions will not be influenced by the slightly different pH storage conditions.
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