Creating Lac- E. coli Mutants
To create Lac negative E. coli mutants for student/faculty use.
1. Do you know how to use the spectrophotometer? The stratalinker?
2. Do you have enough PBS? Do you have enough bacteria?
1. Prepare solution of bacteria and sterile PBS (depending on date, the O.D might differ) in test tube with green cap 1.5 mL bacteria + 1.5 mL sterile PBS Use a blank containing at least 3 mL of PBS, insert into spectrophotometer, and press the arrow up button Take out blank and insert test tube into the spectrophotometer Check if OD is ~0.4 If OD is not ~0.4, remove 1 mL of the solution and add 1 mL of either PBS or bacteria depending on whether OD is higher or lower than 0.4. Repeat until OD is ~0.4.