LIGHT/DARK
Aluminum foil can cover the plate to varying degrees, and the lab bench drawers can be used as a directional light source (through an open key hole). Lights in lab room and environmental rooms will be on 24 hours a day.

COLOR:
Tape colored plastic film to the top of the plates, or make an envelope. We are working on making differently colored fluorescent lights available

cAMP:
The concentration of the stock solution is 10 mM. Vary the concentration by diluting with sodium phosphate buffer in sterile microcentrifuge tube. Students should label their cAMP tube and keep it in cold room 412, to reapply to disk on plate periodically.

pH:
5 standard buffers: pH 4-10 are filter sterilized. Chemicals vary for each:
pH 4 = Potassium Acid Phthalate
pH 5 = Sodium and Potassium Phosphate
pH 7 = Potassium Phosphate
pH 9 = Potassium Phosphate and Sodium Borate
pH 10 = Sodium Borate and Sodium Carbonate

CHEMICAL:
Other treatments can be made available upon request, such as 10 mM caffeine, ethanol (50% or 75 %) and ammonia (10 mM NH4OH or NH4Cl) used with sterile charcoal pieces to create concentration gradient.

CHARCOAL PLATES:
Pieces of charcoal provided in a sterile foil-covered beaker, with forceps. Sterilize forceps by dipping in alcohol, and air-drying before placing charcoal onto agar.

FOOD:
In addition to E. coli, another can be provided upon request, Klebsiella aerogenes, a soil bacteria, pre-inoculated as 3 cm circular area on plate. Liquid cultures of both bacteria are available upon advance notice, for inoculating their own plates.

SLUG STAINING
Use one or both of the two stains provided (sterile): Nile Blue and Neutral Red
Apply 10 uL stain (using micropipet) directly onto a slug and let stain soak into agar at least 10 minutes before moving plates. Restain once again, after 10 minutes.