Marie Curie Workshop Laboratory Manual Clostridial Gene ...

For each integration experiment:Identify which dilution of the integration mixture gave between 5 and 50 colonies per20µl drop on the unsupplemented control plates. Count the number of colonies ineach drop, and calculate the average number per drop. Multiply the average numberof colonies per 20µl drop by 50 and by the appropriate dilution factor to determine thenumber of cfu/ml that were in the integration mixture.Calculate the intron integration frequencies:Frequency as % = erythromycin-resistant cfu/ml x 100total cfu/mlUniversity of Nottingham, Sept ’06 Page 22