E. coli biofilm antibiotic tolerance as a function of temperature (21, 37, 42°C). Cells were grown as biofilms for 6 hours before being transferred to treatment plates for 24 hours. Reported cfu/biofilm data was determined after treatment. a) Cultures grown at 21°C, b) cultures grown at 37°C, and c) cultures grown at 42°C. Black bars = control, dark gray bars = kanamycin (100 ug/ml) challenge, light gray bars = ampicillin (100 ug/ml) challenge. Number at the base of each bar denotes the number of independent replicates. cfu = colony forming unit.