Team:Amsterdam/Notebook/Protocols/Miniprepping

From 2011.igem.org

Revision as of 12:38, 19 September 2011 by Yurivwarmerdam (Talk | contribs)

Miniprepping

We stopped using the [http://www.fermentas.com/templates/files/tiny_mce/coa_pdf/coa_k0502.pdf GeneJET™ Plasmid Miniprep Kit protocol]. We noticed that the optimized purification protocol gave much better results. With this protocol the yield increased dramatically.

Reagents

We used the following reagents from the Fermentas miniprep kit:

  • Resuspension buffer
  • Lysis buffer
  • Neutralization buffer
  • Elution buffer

Other reagents:

  • Isopropanol
  • 70% ethanol

Notes:

  • Check if the RNase A solution has been added to the resuspension solution.
  • Keep the resuspension solution cold.
  • Check lysis and Neutralization buffer for salt precipitation.
  • All centrifugations should be carried out at >12000 g
  • Use 1-5 ml E.coli culture in LB media for purification of high copy plasmids.

Protocol

  1. Resuspend the pelleted cells in 250 µl of the resuspension solution. Pipeting up and down till the cells are completely resuspended. (There is no pellet left).
    2. Note: Ensure RNase A has been added to the resuspension buffer.
  2. Add 250 µl of the lysis solution and mix thoroughly by inverting the tub 4-6 times until the solution becomes viscous and slightly clear.
    3. Note: Do not vortex, do not incubate for more than 5 minutes.
  3. Add 350 µl of the neutralization solution and mix immediately and thoroughly by inverting 4-6 times.
  4. Centrifuge for 5 min to pellet cell debris and chromosomal DNA.
  5. Decadent the supernatant in a new 1,5 ml tube.
  6. Add 650 µl of isopropanol. Invert 4-6 times.
  7. Centrifuge for 5 min.
  8. Remove isopropanol by decanting.
  9. Add 500 µl of 70% ethanol, and remove by decanting.
  10. Let the pellet dry. You can remove some residual ethanol by pippeting.
    11. Note: It is essential all the ethanol is removed.
  11. Resuspend the pellet in 50 µl water or Elution buffer.
    12. Note: This is just a tris-buffer so it will not interfere with the ligation.
  12. Check the concentration of the plasmids on agarose gel or with a Nanodrop.



Retrieved from "http://2011.igem.org/Team:Amsterdam/Notebook/Protocols/Miniprepping"