P1 phages stock

Made an overnight culture in which the phage have to grow.

In the morning, add CaCl₂ at 5mM concentration final.

In 4 tubes:

1. Add 10µl phages culture in 0.1ml of bacterial culture.
2. Add 50µl phages culture in 0.1ml of bacterial culture.
3. Add 100µl phages culture in 0.1ml of bacterial culture.
4. Negative control, just 0.1 of bacterial culture without phage.

Leave 10 minutes at room temperature.

Add 1ml LB in each tube. Add 3ml Agarose 6g/l (at 65°C).

Spread on cold LCA dish + CaCl₂ at 5mM final.

Incubate during 5 to 7hours at 37°C, or during the night at 30°C.

When the carpet becomes limpid, harvest it with a rake in a Falcon tube.

Add 0.5ml of chloroform, and centrifuge 10min at 5000g.

Recover the supernatant and stock it at 4°C.