Chloramphenicol-mobilized Bacillus subtilis transiently expresses resistance to multiple antibiotics, including the glycopeptides phleomycin and bleomycin.

Chloramphenicol exposure triggers transient, spatially regulated expression of multiple antibiotic resistance genes in Bacillus subtilis, including novel resistance to glycopeptides phleomycin and bleomycin.

• Why it matters: Understanding how bacteria regulate resistance genes in response to antibiotics can reveal mechanisms driving resistance spread and help develop strategies to combat antibiotic resistance.
• What they did: Using luciferase reporter constructs fused to resistance gene regulatory regions, the study examined spatiotemporal expression patterns in B. subtilis colonies exposed to subinhibitory chloramphenicol, revealing endogenous translation regulation and resistance mechanisms.
• The result: Pre-exposure to chloramphenicol improved B. subtilis growth against certain antibiotics, and BmrCD was found to confer resistance to glycopeptides, indicating that stalled ribosomes influence resistance beyond translation-targeting drugs.