Identifying transfer barriers for broad host range plasmids in a wastewater microbial community. pKJK5 in wastewaters

We assessed whether the absence of horizontal transfer of genetic material (through conjugation by a broad host range plasmid of the IncP group) can be explained and understood from the genome composition of potential recipients. To that end, we incubated E. coli carrying plasmid pKJK5 containing antimicrobial-resistant genes under antibiotic selection in the presence of a complex microbial community obtained from a wastewater treatment plant. We subsequently compared genomic features of recipient populations to those that did not receive the plasmid and an overall aim to identify genomic barriers to plasmid transfer. We observed distribution patterns of plasmid positives and plasmid negative clades across a wide taxonomic diversity. Even so, only a few genes were shared across plasmid negatives while being absent in plasmid positives, pointing us to important roles of bacterial cell membranes and their structure and biochemical composition.