Team:CU-Boulder/Notebook/Protocols

From 2014.igem.org

(Difference between revisions)
Line 352: Line 352:
*H<sub>2</sub>O                              400 mL
*H<sub>2</sub>O                              400 mL
-
**Bring final volume to 500 mL
+
** *Bring final volume to 500 mL
   
   
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*H<sub>2</sub>O                              800 mL
*H<sub>2</sub>O                              800 mL
-
::Adjust pH to 7.6 with 1M HCl
+
:: *Adjust pH to 7.6 with 1M HCl
-
::Adjust volume to 1 L
+
:: *Adjust volume to 1 L
-
::Store at 3C for up to 3 months
+
:: *Store at 3C for up to 3 months
 +
 +
 +
 +
 +
 +
{{Template:UCB-Main}}
 +
{{UCB-NavBar}}
 +
__FORCETOC__
 +
 +
==Amplification of Phage using Helper Phage==
 +
 +
'''Need'''
 +
*Plate of infectable cells that contain F’ episome
 +
*2.5M NaCl/20% PEG-8000
 +
*1x TBS
 +
 +
'''Day 1'''
 +
#Add a fresh colony of infectable cells to 50mL LB in 125mL flask.
 +
**a. Include phagemid antibiotic only.
 +
**b. Grow at 37°C, 250rpm until OD is between 0.03 and 0.05
 +
#Add the helper phage to a final concentration of 1 x10^8 phage/mL
 +
#Incubate for 60-90 minutes, shaking
 +
#Add Helper Phagemid antibiotic to a high concentration
 +
#Grow for 14-18 hours at 37°C, shaking
 +
 +
'''Day 2'''
 +
#Spin culture at 4,000 x g for 10 minutes
 +
#Transfer supernatant to a fresh conical. Repeat spin on supernatant
 +
#Transfer the upper 90% of supernatant to a new conical
 +
#Add 0.2 volume of 2.5M NaCl/20% PEG-8000 to the new conical. Gently mix
 +
#Incubate at 4°C for at least 60 minutes
 +
#Centrifuge at 12,000 x g for 10 minutes. Carefully decant
 +
#Spin again briefly
 +
#Gently resuspend pellet in 1.6mL 1x TBS
 +
#Aliquot 800ul into 2 microfuge tubes. Proceed with both tubes
 +
#Spin sample for 1 minute to pellet remaining cells. Transfer supernatant to fresh tubes
 +
#Add 160ul of 2.5M NaCl/20% PEG-8000 solution to each
 +
#Let sit at room temperature for 5 minutes
 +
#Spin at 1300 x g for 10 minutes
 +
#Decant the supernatant
 +
#Spin briefly. Remove supernatant with pipet
 +
#Resuspend pellet in 200ul 1x TBS.
 +
**a. If desired, combine contents of both tubes into one
 +
 +
'''2.5M NaCl/20% PEG-8000 (5x)'''
 +
*PEG-8000 100 g
 +
*NaCl 75 g
 +
*H2O 400 mL
 +
* *Bring final volume to 500 mL
 +
 +
'''TBS (1x)'''
 +
*Tris 6.05 g
 +
*NaCl 8.76 g
 +
*H2O 800 mL
 +
* *Adjust pH to 7.6 with 1M HCl
 +
* *Adjust volume to 1 L
 +
 +
 +
 +
 +
 +
 +
 +
==Bacterial Transformation Using Frozen Competent Cells==
 +
 +
'''Before you start'''
 +
*Heat hot plate or water bath to 42°C
 +
*Warm selection plates to 37°C
 +
 +
'''Transformation'''
 +
#Thaw chemically competent cells on ice for 10-15 minutes
 +
#Add 40ul cells to fresh 1.7mL tube
 +
#Add DNA
 +
**a. If using a ligation product add up to 10ul of sample
 +
**b. If using supercoiled plasmid add 100ng
 +
#Incubate on ice for 30 minutes
 +
#Heat shock cells on hot plate (or water bath) for 30-45s* @ 42°C
 +
#Incubate on ice for 2-5 minutes
 +
#Add 200 μL SOC and shake gently for 1-2 hours @ 37° C
 +
*a.('''Note''': Can also recover in 960ul. After recovery, gently spin cells and remove supernatant. Resuspend in 200ul LB)
 +
#Plate 100-200ul cells onto selection plates
 +
**a. If high efficiency is expected, we suggest also plating a 1:10 dilution
 +
#Once dry, turn upside down (agar on top) and incubate overnight @ 37° C
 +
 +
* *Optimal timing depends on cells
 +
 +
 +
'''SOC (1L)'''
 +
*Tryptone 20 g
 +
*Yeast Extract 5 g
 +
*MgSO4 4.8 g
 +
*Dextrose 3.6 g
 +
*NaCl 0.5 g
 +
*KCl 0.186 g
 +
 +
 +
 +
 +
 +
 +
 +
==Bacterial Conjugation==
 +
 +
'''Need'''
 +
*Donor cells: Cells already containing F’ episome
 +
*Recipient cells: Cells with a resistance marker that is absent from donor cells
 +
*Double selection plate containing antibiotic to select for F’ episome and a second antibiotic to select for the recipient cells
 +
 +
'''Day 1'''
 +
#Set up liquid overnight of '''donor''' cells. Include antibiotic
 +
#Set up liquid overnight of '''recipient''' cells. Include antibiotic
 +
 +
'''Day 2'''
 +
#Mix 500ul of each overnight sample in a new tube. Mix by pipetting or flicking
 +
#Incubate for 30 minutes at 37°C, shaking
 +
#Plate 100ul onto double selection plate
 +
*a.We advise also plating a 1:10 dilution
 +
#Incubate at 37°C
 +
 +
http://inst.bact.wisc.edu/inst/index.php?module=Book&func=displayarticle&art_id=128
 +
 +
 +
 +
 +
 +
 +
 +
==Making Chemically Competent Bacteria==
 +
 +
'''To prepare for Day 2'''
 +
#Set centrifuge to 4°C
 +
#MgCl2 and CaCl2 solutions
 +
#Thaw DMSO
 +
#Chill tubes
 +
#Acquire liquid nitrogen or dry ice
 +
 +
'''Day 1'''
 +
#Grow cells O/N
 +
 +
'''Day 2'''
 +
#Add 0.5mL of the overnight culture to 50mL LB
 +
#Grow until OD is between 0.2 and 0.4
 +
#Incubate on ice for 30 minutes
 +
#Centrifuge for 10 minutes at 2700 x g and 4°C
 +
#Decant. Dry upside down on a paper towel for 1 minute
 +
#Completely resuspend in 30mL 0.8M MgCl2, 0.2M CaCl2
 +
**a. Gently vortex
 +
#Centrifuge for 10 minutes at 2700 x g and 4°C
 +
#Decant. Dry upside down on a paper towel for 1 minute
 +
#Fully resuspend in 2mL of 0.1M CaCl2
 +
# Chill sample on ice. Add 70ul DMSO, keeping the sample tube on ice
 +
#Swirl to mix
 +
#Incubate on ice for 15 minutes
 +
#Add 70ul DMSO, swirl to mix, keeping the sample tube on ice
 +
#Dispense 200ul into pre-chilled 1.7mL tubes
 +
#Snap freeze with liquid nitrogen or dry ice
 +
#Store at -80°C until ready to use
 +
 +
 +
 +
 +
 +
 +
==Isolation of single-stranded phagemid DNA using M13K07 Helper Phage==
   
   
 +
'''Need'''
 +
 +
*Fresh plate of infectable cells (contain F’ episome)
 +
*2.5M NaCl/20% PEG-8000
 +
*TBS, TE, phenol, phenol/chloroform, chloroform
 +
 +
 +
 +
'''Day 1'''
 +
 +
1.      Add a fresh colony to 50mL LB in 125mL flask. Grow at 37°C, 250rpm until OD is between 0.03 and 0.05
 +
2.      Add M13KO7 helper phage to a final concentration of 1 x10^8 phage/mL*
 +
3.      Continue shaking for 60-90 minutes
 +
4.      Add Kanamycin to final concentration of 70ug/mL
 +
5.      Grow for 14-18 hours at 37°C, 250rpm
 +
 +
* *Can use a different helper phage if needed. In step 4, add the antibiotic specific to the Helper Phagemid
 +
 +
'''Day 2'''
 +
 +
1.      Spin culture at 4,000 x g for 10 minutes
 +
2.      Transfer supernatant to a fresh conical. Repeat spin on supernatant
 +
3.      Transfer the upper 90% of supernatant to a new conical
 +
4.      Add 0.2 volume of 2.5M NaCl/20% PEG-8000 to the new conical. Gently mix
 +
5.      Incubate at 4°C for at least 60 minutes
 +
6.      Centrifuge at 12,000 x g for 10 minutes. Carefully decant
 +
7.      Spin again briefly
 +
8.      Gently resuspend pellet in 1.6mL 1x TBS
 +
9.      Aliquot 800ul into 2 microfuge tubes. Proceed with both tubes
 +
10.  Spin sample for 1 minute to pellet remaining cells. Transfer supernatant to fresh tubes
 +
11.  Add 160ul of 2.5M NaCl/20% PEG-8000 solution to each
 +
12.  Let sit at room temperature for 5 minutes
 +
13.  Spin at 1300 x g for 10 minutes
 +
14.  Decant the supernatant
 +
15.  Spin briefly. Remove supernatant with pipet
 +
16.  Resuspend pellets in 300ul TE
 +
17.  Phenol extraction: add 300ul phenol. Vortex for 15 seconds
 +
*a.      Let sit for 15 minutes. Spin for 10 minutes
 +
18.  Add H2O so volume samples is about 300ul
 +
19.  Phenol/chloroform extraction*: add 300ul PCIA
 +
*a.      Vortex for 15 seconds. Spin for 10 minutes
 +
20.  Repeat Phenol/Chloroform extraction
 +
21.  Chloroform extraction*: add 300ul chloroform
 +
*a.      Vortex 15 seconds. Spin for 10 minutes
 +
22.  Add 30ul 2.5M NaAc (pH 4.8)
 +
23.  Add 2-2.5 volumes ethanol
 +
24.  Let precipitate for ~2 hours at -20°C
 +
25.  Spin for 1 minute
 +
26.  Decant supernatant
 +
27.  Resuspend in 25-50ul TE
 +
 +
* *Performing steps at 4°C helps with separation
 +
 +
 +
'''2.5M NaCl/20% PEG-8000 (5x)'''
 +
 +
*PEG-800    100g
 +
*NaCl  75g
 +
*H<sub>2</sub>O    400mL
 +
 +
** *Bring final volume to 500 mL
 +
'''TBS (1x)'''
 +
 +
* Tris 6.05 g
 +
 +
*NaCl 8.76 g
 +
*H<sub>2</sub>O 800 mL
-
{{Template:UCB-Footer}}
+
** *Adjust pH to 7.6 with 1M HCl
 +
** *Adjust volume to 1 L

Revision as of 02:50, 4 October 2014


Contents

Amplification of Phage using Helper Phage

Need

  • Plate of infectable cells that contain F’ episome
  • 2.5M NaCl/20% PEG-8000
  • 1x TBS

Day 1

  1. Add a fresh colony of infectable cells to 50mL LB in 125mL flask.
    • a. Include phagemid antibiotic only.
    • b. Grow at 37°C, 250rpm until OD is between 0.03 and 0.05
  1. Add the helper phage to a final concentration of 1 x10^8 phage/mL
  2. Incubate for 60-90 minutes, shaking
  3. Add Helper Phagemid antibiotic to a high concentration
  4. Grow for 14-18 hours at 37°C, shaking

Day 2

  1. Spin culture at 4,000 x g for 10 minutes
  2. Transfer supernatant to a fresh conical. Repeat spin on supernatant
  3. Transfer the upper 90% of supernatant to a new conical
  4. Add 0.2 volume of 2.5M NaCl/20% PEG-8000 to the new conical. Gently mix
  5. Incubate at 4°C for at least 60 minutes
  6. Centrifuge at 12,000 x g for 10 minutes. Carefully decant
  7. Spin again briefly
  8. Gently resuspend pellet in 1.6mL 1x TBS
  9. Aliquot 800ul into 2 microfuge tubes. Proceed with both tubes
  10. Spin sample for 1 minute to pellet remaining cells. Transfer supernatant to fresh tubes
  11. Add 160ul of 2.5M NaCl/20% PEG-8000 solution to each
  12. Let sit at room temperature for 5 minutes
  13. Spin at 1300 x g for 10 minutes
  14. Decant the supernatant
  15. Spin briefly. Remove supernatant with pipet
  16. Resuspend pellet in 200ul 1x TBS.
    • a. If desired, combine contents of both tubes into one

2.5M NaCl/20% PEG-8000 (5x)

  • PEG-8000 100 g
  • NaCl 75 g
  • H2O 400 mL
  • Bring final volume to 500 mL

TBS (1x)

  • Tris 6.05 g
  • NaCl 8.76 g
  • H2O 800 mL
  • Adjust pH to 7.6 with 1M HCl
  • Adjust volume to 1 L




Bacterial Transformation Using Frozen Competent Cells

Before you start

  • Heat hot plate or water bath to 42°C
  • Warm selection plates to 37°C

Transformation

  1. Thaw chemically competent cells on ice for 10-15 minutes
  2. Add 40ul cells to fresh 1.7mL tube
  3. Add DNA
    • a. If using a ligation product add up to 10ul of sample
    • b. If using supercoiled plasmid add 100ng
  1. Incubate on ice for 30 minutes
  2. Heat shock cells on hot plate (or water bath) for 30-45s* @ 42°C
  3. Incubate on ice for 2-5 minutes
  4. Add 200 μL SOC and shake gently for 1-2 hours @ 37° C
  • a.(Note: Can also recover in 960ul. After recovery, gently spin cells and remove supernatant. Resuspend in 200ul LB)
  1. Plate 100-200ul cells onto selection plates
    • a. If high efficiency is expected, we suggest also plating a 1:10 dilution
  1. Once dry, turn upside down (agar on top) and incubate overnight @ 37° C
  • *Optimal timing depends on cells


SOC (1L)

  • Tryptone 20 g
  • Yeast Extract 5 g
  • MgSO4 4.8 g
  • Dextrose 3.6 g
  • NaCl 0.5 g
  • KCl 0.186 g




Bacterial Conjugation

Need

  • Donor cells: Cells already containing F’ episome
  • Recipient cells: Cells with a resistance marker that is absent from donor cells
  • Double selection plate containing antibiotic to select for F’ episome and a second antibiotic to select for the recipient cells

Day 1

  1. Set up liquid overnight of donor cells. Include antibiotic
  2. Set up liquid overnight of recipient cells. Include antibiotic

Day 2

  1. Mix 500ul of each overnight sample in a new tube. Mix by pipetting or flicking
  2. Incubate for 30 minutes at 37°C, shaking
  3. Plate 100ul onto double selection plate
  • a.We advise also plating a 1:10 dilution
  1. Incubate at 37°C

http://inst.bact.wisc.edu/inst/index.php?module=Book&func=displayarticle&art_id=128




Making Chemically Competent Bacteria

To prepare for Day 2

  1. Set centrifuge to 4°C
  2. MgCl2 and CaCl2 solutions
  3. Thaw DMSO
  4. Chill tubes
  5. Acquire liquid nitrogen or dry ice

Day 1

  1. Grow cells O/N

Day 2

  1. Add 0.5mL of the overnight culture to 50mL LB
  2. Grow until OD is between 0.2 and 0.4
  3. Incubate on ice for 30 minutes
  4. Centrifuge for 10 minutes at 2700 x g and 4°C
  5. Decant. Dry upside down on a paper towel for 1 minute
  6. Completely resuspend in 30mL 0.8M MgCl2, 0.2M CaCl2
    • a. Gently vortex
  1. Centrifuge for 10 minutes at 2700 x g and 4°C
  2. Decant. Dry upside down on a paper towel for 1 minute
  3. Fully resuspend in 2mL of 0.1M CaCl2
  4. Chill sample on ice. Add 70ul DMSO, keeping the sample tube on ice
  5. Swirl to mix
  6. Incubate on ice for 15 minutes
  7. Add 70ul DMSO, swirl to mix, keeping the sample tube on ice
  8. Dispense 200ul into pre-chilled 1.7mL tubes
  9. Snap freeze with liquid nitrogen or dry ice
  10. Store at -80°C until ready to use




Isolation of single-stranded phagemid DNA using M13K07 Helper Phage

Need

  • Fresh plate of infectable cells (contain F’ episome)
  • 2.5M NaCl/20% PEG-8000
  • TBS, TE, phenol, phenol/chloroform, chloroform


Day 1

1. Add a fresh colony to 50mL LB in 125mL flask. Grow at 37°C, 250rpm until OD is between 0.03 and 0.05

2. Add M13KO7 helper phage to a final concentration of 1 x10^8 phage/mL*

3. Continue shaking for 60-90 minutes

4. Add Kanamycin to final concentration of 70ug/mL

5. Grow for 14-18 hours at 37°C, 250rpm

  • *Can use a different helper phage if needed. In step 4, add the antibiotic specific to the Helper Phagemid


Day 2

1. Spin culture at 4,000 x g for 10 minutes

2. Transfer supernatant to a fresh conical. Repeat spin on supernatant

3. Transfer the upper 90% of supernatant to a new conical

4. Add 0.2 volume of 2.5M NaCl/20% PEG-8000 to the new conical. Gently mix

5. Incubate at 4°C for at least 60 minutes

6. Centrifuge at 12,000 x g for 10 minutes. Carefully decant

7. Spin again briefly

8. Gently resuspend pellet in 1.6mL 1x TBS

9. Aliquot 800ul into 2 microfuge tubes. Proceed with both tubes

10. Spin sample for 1 minute to pellet remaining cells. Transfer supernatant to fresh tubes

11. Add 160ul of 2.5M NaCl/20% PEG-8000 solution to each

12. Let sit at room temperature for 5 minutes

13. Spin at 1300 x g for 10 minutes

14. Decant the supernatant

15. Spin briefly. Remove supernatant with pipet

16. Resuspend pellets in 300ul TE

17. Phenol extraction: add 300ul phenol. Vortex for 15 seconds

  • a. Let sit for 15 minutes. Spin for 10 minutes

18. Add H2O so volume samples is about 300ul

19. Phenol/chloroform extraction*: add 300ul PCIA

  • a. Vortex for 15 seconds. Spin for 10 minutes

20. Repeat Phenol/Chloroform extraction

21. Chloroform extraction*: add 300ul chloroform

  • a. Vortex 15 seconds. Spin for 10 minutes

22. Add 30ul 2.5M NaAc (pH 4.8)

23. Add 2-2.5 volumes ethanol

24. Let precipitate for ~2 hours at -20°C

25. Spin for 1 minute

26. Decant supernatant

27. Resuspend in 25-50ul TE

  • *Performing steps at 4°C helps with separation



2.5M NaCl/20% PEG-8000 (5x)

  • PEG-800 100g
  • NaCl 75g
  • H2O 400mL
    • *Bring final volume to 500 mL

TBS (1x)

  • Tris 6.05 g
  • NaCl 8.76 g
  • H2O 800 mL
    • *Adjust pH to 7.6 with 1M HCl
    • *Adjust volume to 1 L





M13 Amplification


This protocol is to make more M13 phages.


Need

  • Fresh plate of infectable cells (contain F’ episome)


Day 1

1. Grow liquid overnight culture of infectable cells


Day 2

1. Add 200ul overnight culture to 20mL LB in a 250mL flask

2. Add 1ul phage suspension

3. Incubate for 4-5 hours at 37°C, 250rpm

4. Centrifuge for 10 minutes at 4500 x g

5. Transfer supernatant to a new tube.

6. Repeat centrifugation on supernatant

7. Transfer top 16mL of supernatant to a new tube

8. Add 4mL of 2.5M NaCl/20% PEG-8000. Briefly mix

9. Precipitate phage for 1 hour or overnight at 4°C

10. Centrifuge for 15 minutes at 12000 x g. Decant supernatant

  • a. Spin briefly. Remove residual supernatant with pipet

11. Resuspend pellet in 1mL 1x TBS. Transfer to 1.7mL tube

12. Spin briefly to remove cell debris

13. Transfer supernatant to a new tube

14. Add 200ul of 2.5M NaCl/20% PEG-8000

15. Incubate on ice for 15-60 minutes

16. Spin for 10 minutes at 12000-14000 rpm. Discard supernatant

17. Briefly spin. Remove supernatant with pipette

18. Resuspend pellet in 200uL TBS

19. For long term storage at -20C, add 200uL glycerol



2.5M NaCl/20% PEG-8000 (5x)

  • PEG-8000 100 g
  • NaCl 75 g
  • H2O 400 mL
    • *Bring final volume to 500 mL


TBS (1x)

  • Tris 6.05 g
  • NaCl 8.76 g
  • H2O 800 mL
*Adjust pH to 7.6 with 1M HCl
*Adjust volume to 1 L
*Store at 3C for up to 3 months





Amplification of Phage using Helper Phage

Need

  • Plate of infectable cells that contain F’ episome
  • 2.5M NaCl/20% PEG-8000
  • 1x TBS

Day 1

  1. Add a fresh colony of infectable cells to 50mL LB in 125mL flask.
    • a. Include phagemid antibiotic only.
    • b. Grow at 37°C, 250rpm until OD is between 0.03 and 0.05
  1. Add the helper phage to a final concentration of 1 x10^8 phage/mL
  2. Incubate for 60-90 minutes, shaking
  3. Add Helper Phagemid antibiotic to a high concentration
  4. Grow for 14-18 hours at 37°C, shaking

Day 2

  1. Spin culture at 4,000 x g for 10 minutes
  2. Transfer supernatant to a fresh conical. Repeat spin on supernatant
  3. Transfer the upper 90% of supernatant to a new conical
  4. Add 0.2 volume of 2.5M NaCl/20% PEG-8000 to the new conical. Gently mix
  5. Incubate at 4°C for at least 60 minutes
  6. Centrifuge at 12,000 x g for 10 minutes. Carefully decant
  7. Spin again briefly
  8. Gently resuspend pellet in 1.6mL 1x TBS
  9. Aliquot 800ul into 2 microfuge tubes. Proceed with both tubes
  10. Spin sample for 1 minute to pellet remaining cells. Transfer supernatant to fresh tubes
  11. Add 160ul of 2.5M NaCl/20% PEG-8000 solution to each
  12. Let sit at room temperature for 5 minutes
  13. Spin at 1300 x g for 10 minutes
  14. Decant the supernatant
  15. Spin briefly. Remove supernatant with pipet
  16. Resuspend pellet in 200ul 1x TBS.
    • a. If desired, combine contents of both tubes into one

2.5M NaCl/20% PEG-8000 (5x)

  • PEG-8000 100 g
  • NaCl 75 g
  • H2O 400 mL
  • *Bring final volume to 500 mL

TBS (1x)

  • Tris 6.05 g
  • NaCl 8.76 g
  • H2O 800 mL
  • *Adjust pH to 7.6 with 1M HCl
  • *Adjust volume to 1 L




Bacterial Transformation Using Frozen Competent Cells

Before you start

  • Heat hot plate or water bath to 42°C
  • Warm selection plates to 37°C

Transformation

  1. Thaw chemically competent cells on ice for 10-15 minutes
  2. Add 40ul cells to fresh 1.7mL tube
  3. Add DNA
    • a. If using a ligation product add up to 10ul of sample
    • b. If using supercoiled plasmid add 100ng
  1. Incubate on ice for 30 minutes
  2. Heat shock cells on hot plate (or water bath) for 30-45s* @ 42°C
  3. Incubate on ice for 2-5 minutes
  4. Add 200 μL SOC and shake gently for 1-2 hours @ 37° C
  • a.(Note: Can also recover in 960ul. After recovery, gently spin cells and remove supernatant. Resuspend in 200ul LB)
  1. Plate 100-200ul cells onto selection plates
    • a. If high efficiency is expected, we suggest also plating a 1:10 dilution
  1. Once dry, turn upside down (agar on top) and incubate overnight @ 37° C
  • *Optimal timing depends on cells


SOC (1L)

  • Tryptone 20 g
  • Yeast Extract 5 g
  • MgSO4 4.8 g
  • Dextrose 3.6 g
  • NaCl 0.5 g
  • KCl 0.186 g




Bacterial Conjugation

Need

  • Donor cells: Cells already containing F’ episome
  • Recipient cells: Cells with a resistance marker that is absent from donor cells
  • Double selection plate containing antibiotic to select for F’ episome and a second antibiotic to select for the recipient cells

Day 1

  1. Set up liquid overnight of donor cells. Include antibiotic
  2. Set up liquid overnight of recipient cells. Include antibiotic

Day 2

  1. Mix 500ul of each overnight sample in a new tube. Mix by pipetting or flicking
  2. Incubate for 30 minutes at 37°C, shaking
  3. Plate 100ul onto double selection plate
  • a.We advise also plating a 1:10 dilution
  1. Incubate at 37°C

http://inst.bact.wisc.edu/inst/index.php?module=Book&func=displayarticle&art_id=128




Making Chemically Competent Bacteria

To prepare for Day 2

  1. Set centrifuge to 4°C
  2. MgCl2 and CaCl2 solutions
  3. Thaw DMSO
  4. Chill tubes
  5. Acquire liquid nitrogen or dry ice

Day 1

  1. Grow cells O/N

Day 2

  1. Add 0.5mL of the overnight culture to 50mL LB
  2. Grow until OD is between 0.2 and 0.4
  3. Incubate on ice for 30 minutes
  4. Centrifuge for 10 minutes at 2700 x g and 4°C
  5. Decant. Dry upside down on a paper towel for 1 minute
  6. Completely resuspend in 30mL 0.8M MgCl2, 0.2M CaCl2
    • a. Gently vortex
  1. Centrifuge for 10 minutes at 2700 x g and 4°C
  2. Decant. Dry upside down on a paper towel for 1 minute
  3. Fully resuspend in 2mL of 0.1M CaCl2
  4. Chill sample on ice. Add 70ul DMSO, keeping the sample tube on ice
  5. Swirl to mix
  6. Incubate on ice for 15 minutes
  7. Add 70ul DMSO, swirl to mix, keeping the sample tube on ice
  8. Dispense 200ul into pre-chilled 1.7mL tubes
  9. Snap freeze with liquid nitrogen or dry ice
  10. Store at -80°C until ready to use




Isolation of single-stranded phagemid DNA using M13K07 Helper Phage

Need

  • Fresh plate of infectable cells (contain F’ episome)
  • 2.5M NaCl/20% PEG-8000
  • TBS, TE, phenol, phenol/chloroform, chloroform


Day 1

1. Add a fresh colony to 50mL LB in 125mL flask. Grow at 37°C, 250rpm until OD is between 0.03 and 0.05 2. Add M13KO7 helper phage to a final concentration of 1 x10^8 phage/mL* 3. Continue shaking for 60-90 minutes 4. Add Kanamycin to final concentration of 70ug/mL 5. Grow for 14-18 hours at 37°C, 250rpm

  • *Can use a different helper phage if needed. In step 4, add the antibiotic specific to the Helper Phagemid

Day 2

1. Spin culture at 4,000 x g for 10 minutes 2. Transfer supernatant to a fresh conical. Repeat spin on supernatant 3. Transfer the upper 90% of supernatant to a new conical 4. Add 0.2 volume of 2.5M NaCl/20% PEG-8000 to the new conical. Gently mix 5. Incubate at 4°C for at least 60 minutes 6. Centrifuge at 12,000 x g for 10 minutes. Carefully decant 7. Spin again briefly 8. Gently resuspend pellet in 1.6mL 1x TBS 9. Aliquot 800ul into 2 microfuge tubes. Proceed with both tubes 10. Spin sample for 1 minute to pellet remaining cells. Transfer supernatant to fresh tubes 11. Add 160ul of 2.5M NaCl/20% PEG-8000 solution to each 12. Let sit at room temperature for 5 minutes 13. Spin at 1300 x g for 10 minutes 14. Decant the supernatant 15. Spin briefly. Remove supernatant with pipet 16. Resuspend pellets in 300ul TE 17. Phenol extraction: add 300ul phenol. Vortex for 15 seconds

  • a. Let sit for 15 minutes. Spin for 10 minutes

18. Add H2O so volume samples is about 300ul 19. Phenol/chloroform extraction*: add 300ul PCIA

  • a. Vortex for 15 seconds. Spin for 10 minutes

20. Repeat Phenol/Chloroform extraction 21. Chloroform extraction*: add 300ul chloroform

  • a. Vortex 15 seconds. Spin for 10 minutes

22. Add 30ul 2.5M NaAc (pH 4.8) 23. Add 2-2.5 volumes ethanol 24. Let precipitate for ~2 hours at -20°C 25. Spin for 1 minute 26. Decant supernatant 27. Resuspend in 25-50ul TE

  • *Performing steps at 4°C helps with separation


2.5M NaCl/20% PEG-8000 (5x)

  • PEG-800 100g
  • NaCl 75g
  • H2O 400mL
    • *Bring final volume to 500 mL

TBS (1x)

  • Tris 6.05 g
  • NaCl 8.76 g
  • H2O 800 mL
    • *Adjust pH to 7.6 with 1M HCl
    • *Adjust volume to 1 L
Retrieved from "http://2014.igem.org/Team:CU-Boulder/Notebook/Protocols"