Plasmids transformation :
Add 20 ng of plasmid to 100 µL of competent cells thawed in ice
Incubate 30-45 min in ice
Thermal shock : put tubes in the Thermomixer at 42°C during 2 min
Incubate 5 min in ice
Add 900 µL of LB
Incubate 1 hour at 37°C with agitation
Spread 100 µL on LB limp (with antibiotic)
To make negative control, follow the same procedure but without add plasmids and spread 300 µL
Ligation transformation:
Add 20 ng of ligation’s product to 100 µL of competent cells thawed in ice
Incubate 30-45 min in ice
Thermal shock : put tubes in the Thermomixer at 42°C during 2 min
Incubate 5 min in ice
Add 900 µL of LB
Incubate 1 hour at 37°C with agitation
Centrifuge 5 min at 5000 rpm
Eliminate 850 µL of medium
Suspend the pellet
Spread 150 µL on LB limp (with antibiotic)
To make negative control, follow the same procedure but without add plasmids and spread 300 µL

Make a culture of your bacteria in LB medium and let it grow until bacteria are in exponential phase (OD600 = 0.5).
Cells are cold centrifuge 10 min at 3500 rpm.
The pellet is slowly suspended in 80 mL of Tfb1 buffer (300mM KOAc, 0.05M MnCl2, 0.1M KCl, 0.01M
CaCl2, 15% Glycerol (see next section “Preparation of Tbf1 and Tbf2 buffer”).
After another 5 min cold centrifugation at 3500 rpm, the pullet is suspended in 8 mL of Tbf2 Buffer
(0.01mM NaMOPS pH 7, 0.075M CaCl2, 0.01M KCl, 15% Glycerol)
Incubate 15 min in ice. Aliquot 200µL of cell suspension in sterile Eppendorf tubes. The cell
suspension is conserved at -80°C.

For 200 mL of culture:
Preparation of 80 mL of Tbf1 Buffer:

KAc 1M	2.4 mL
MnCl2 0.5M	8 mL
KCl 1 M	8 mL
CaCl2 0.1M	8 mL
Gly 80%	15 mL
H2O	38.6 mL

Preparation of 8 mL of Tbf2 Buffer:

NaMOPS 0.2M	400 µL
CaCl2 0.1M	6 mL
KCl 1 M	8 mL
Gly 80%	1.5 mL
KCl 1M	80 µL
H2O	500 µL

50% glycerol	6.25 mL Glycerol 80%
20 mM EDTA	0.4 mL EDTA 0.5 M
0.05% Bromophenol blue	≈0.05g Bromophenol blue
0.05% Xylene cyanol	≈0.05g xylene cyanol
1% SDS	1 mL SDS 10%

DNA	Between 50 and 100 ng
EcoRI-HF	0.2 µL
PstI	0.2 µL
10X NEBuffer 2	2 µL
100X BSA	0.2 µL
H2O	To 20 µL

Incubate all digest reactions at 37°C for 1 hour and then add 3 µL of SES 4X and migrate 30 min at
150V on a 1% agarose gel.

Upstream part :

Upstream part plasmid	500 ng
EcoRI-HF	1 µL
PstI	1 µL
10X NEBuffer 2	2.5 µL
100X BSA	0.5 µL
H2O	To 50 µL

Downstream part :

Downstream part plasmid	500 ng
Xba I	1 µL
Spe I	1 µL
10X NEBuffer 2	2.5 µL
100X BSA	0.5 µL
H2O	To 50 µL

Destination plasmid:

Destination plasmid	500 ng
EcoRI-HF	1 µL
PstI	1 µL
DpnI	1 µL
10X NEBuffer 2	2.5 µL
100X BSA	0.5 µL
H2O	To 50 µL

Incubate the three restriction digest reactions at 37°C for 10 minutes and then heat inactivate at 80°C for 20 minutes.

Upstream part digestion	2 µL
Dowstream part digestion	2 µL
Destination plasmid	2 µL
10X T4 DNA ligase buffer	2 µL
T4 DNA ligase	1 µL
H2O	11 µL

Incubate at RT for 1 hour.