Wild type and ∆crcB were grown directly next to each other at varying levels of fluoride. As described in literature, ∆crcB should not grow when exposed to fluoride levels over 500µM. Unexpectedly, ∆crcB did grow on high levels of fluoride when placed on the same plates as wild type E. coli. Without wild type E. coli, no growth of ∆crcB was seen on 1mM and 2mM fluoride.
