Genetic Transfer Systems for Delivery of Plasmid Deoxyribonucleic Acid to Lactobacillus acidophilus ADH: Conjugation, Electroporation, and Transduction

Abstract

Lactobacillus acidophilus ADH is a bacteriocin-producing human isolate that adheres to human fetal intestinal cells and human ileal cells. We have employed both electroporation and conjugation methodologies to transfer various plasraids to L. acidophilus ADH. Furthermore, we have demonstrated transduction of plasmid DNA within this strain by a temperate bacteriophage (~adh) harbored by L. acidophilus ADH. Plasmid pGK12 was introduced into strain ADH by elec-l~aOmmtiOn at frequencies as high as 3.3 x sformants/~tg of plasmid DNA. Transconjugants of strain ADH were recovered at frequencies of 10 -2 (pAMB1), 10 --4 (pVA797 ::Tn917), and 1 (pVA797) per donor cell after filter-matings with Lactococcus lactis ssp. lactis.