生物行移动版

Wednesday, October 01, 2003

Description

REFERENCE: Molecular Cloning: A Laboratory Manual, 2nd ed., pp.1.25-1.28.

Procedure

1. Grow up a 5 ml culture overnight in the presence of the appropriate antibiotic.

2. Harvest 1.5 ml of culture by centrifugation in an Eppendorf tube.

3. Resuspend the pellet in 100 l of ice-cold solution 1.

4. Store for 5 minutes at room temperature.

5. Add 200 l of solution 2 and mix the contents by inverting the tube rapidly two or three times. Do not vortex.

6. Store for 5 minutes on ice.

7. Add 150 ul of ice-cold solution 3 and mix by vortexing in an inverted position.

8. Store for 5 minutes on ice.

9. Centrifuge for 5 minutes in a Eppendorf centrifuge at 4C.

10. Transfer supernatant to a fresh tube and add an equal volume of phenol/chloroform. Mix by vortexing the tube and centrifuge for 2 minutes in an eppendorf centrifuge at room temperature.

11. Transfer the top layer to a fresh tube and add two volumes of ethanol. Vortex gently and let stand at room temperature for 2 minutes.

12. Centrifuge for 5 minutes in an Eppendorf centrifuge at 4C.

13. Remove supernatant and add 1 ml of 70% ethanol. Vortex briefly and recentrifuge.

14. Remove supernatant and dry the pellet briefly in a vacuum dessicator.

15. Add 50 l of TE (pH 8.0) containing DNase-free pancreatic RNase (20 l/ml).

Recipes

1. TE buffer 50 mM glucose, 25 mM Tris-Cl (pH 8.0), 10mM EDTA (pH 8.0); filter sterilized and stored at 4C.

2. 0.2N NaOH (freshly diluted from 10N stock), 1% SDS; This solution should be made up fresh on the day of use.

3. 3 M potassium and 5 M acetate. Store at 4C. 60 ml of 5 mM potassium acetate 11.5 ml of glacial acetic acid 28.5 ml of H2O

Supplies

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