FAQ 13: What do I do with the tube containing the “gel-like stuff” in it when you send me a strain or plasmid?

Answer 13: We send our strains and plasmids out as “stabs”. A stab is a small vial containing nutrient medium like that used to make petri plates. We use a sterile loop to innoculate the stab with the strain you request. The strain can survive for years in such a slant although evolution can occur over time so we recommend that you make a glycerol stock (see FAQ 12). When you receive your strain, simply take a sterile loop and plunge it into the center of your stab. Good practice is to now streak it out for a single colony on a selective plate. For example if we sent you a strain containing pSIM5, steak out on a L+Cm (20µg/ml) agar plate or if the strain contains no drug resistance, an LB plate will do. Remember to incubate the plate at 32°!  In the pSIM5 case, you should next grow a liquid culture (at 32°) from a single colony and make a plasmid prep (mini or midi is fine) so you have a stock of pSIM5 to put into whatever strains you wish. Always remember to make a glycerol stock of the strains we send for long term storage (see FAQ 12).