Enterococcus faecalis Gene Transfer under Natural Conditions in Municipal Sewage Water Treatment Plants

摘要: Received 2 October 1997/Accepted 12 November 1997 The ability of Enterococcus faecalis to transfer various genetic elements under natural conditions was tested in two municipal sewage water treatment plants. Experiments activated sludge basins the plants were performed a microcosm which allowed us work sterile conditions; experiments anoxic digestors dialysis bags. We used following naturally occurring elements: pAD1 and pIP1017 (two so-called sex pheromone plasmids with restricted host ranges, are transferred at high rates laboratory conditions); pIP501 (a resistance plasmid possessing broad range for grampositive bacteria, is low Tn916 conjugative transposon gram-positive bacteria very gram-negative bacteria). rate between different strains E. was, compared that conditions, least 10 5 -fold lower plasmids, 100-fold pIP501, 10-fold Tn916. In no case from another bacterial species detected. By determining dependence on concentration extrapolating actual concentrations plant, we calculated maximum number events plant city Regensburg ranged 8 per 4 h, indicating gene should take place conditions.