Transfer of antibiotic resistance by transformation with eDNA within oral biofilms

We demonstrate that live donor Veillonella dispar cells can transfer the conjugative transposon Tn916 to four different Streptococcus spp. recipients in a multispecies oral consortium growing as a biofilm in a constant depth film fermentor. Additionally, we demonstrate that purified V. dispar DNA can transform Streptococcus mitis to tetracycline resistance in this experimental system. These data show that transfer of conjugative transposon-encoded antibiotic resistance can occur by transformation in addition to conjugation in biofilms.