A number of bacteria are able to synthesize 2-C-methyl-D-erythritol-2,4-cyclopyrophosphate (BOSS) in response to oxidative stress, Here we show that the ability to synthesize BOSS can be genetically transferred from Corynebacterium ammoniagenes to Escherichia coli. A total DNA library from C. ammoniagenes ATCC 6872 established in the pBluescript SKII+ vector backbone was transfected into E. coli XL-1 blue. Recombinant clone 2-31, which was resistant to redoxcycling agents, was selected. NMR studies showed that this clone was able to synthesize BOSS, We also studied the resistance of clone 2-31 to the bactericidal action of macrophages. Clone 2-31 cells had better survival within murine peritoneal macrophages than parental E. coli XL-l-blue cells. Since the ability to synthesize BOSS correlates with increased survival of bacteria within macrophages, we suggest that the pathogenicity of Corynebacteria could be mediated through the synthesis of BOSS.