IncP‐type plasmids carrying genes for antibiotic resistance or for aromatic compound degradation are prevalent in sequenced Aromatoleum and Thauera strains. (15th November 2022) - Lo, Hao‐Yu
Abstract: Self‐transferable plasmids of the incompatibility group P‐1 (IncP‐1) are considered important carriers of genes for antibiotic resistance and other adaptive functions. In the laboratory, these plasmids have a broad host range; however, little is known about their in situ host profile. In this study, we discovered that Thauera aromatica K172 T, a facultative denitrifying microorganism capable of degrading various aromatic compounds, contains a plasmid highly similar to the IncP‐1 ε archetype pKJK5. The plasmid harbours multiple antibiotic resistance genes and is maintained in strain K172 T for at least 1000 generations without selection pressure from antibiotics. In a subsequent search, we found additional nine IncP‐type plasmids in a total of 40 sequenced genomes of the closely related genera Aromatoleum and Thauera . Six of these plasmids form a novel IncP‐1 subgroup designated θ, four of which carry genes for anaerobic or aerobic degradation of aromatic compounds. Pentanucleotide sequence analyses ( k ‐mer profiling) indicated that Aromatoleum spp. and Thauera spp. are among the most suitable hosts for the θ plasmids. Our results highlight the importance of IncP‐1 plasmids for the genetic adaptation of these common facultative denitrifying bacteria and provide novel insights into the in situ host profile of these plasmids.