Occurrence of Plasmids in the Aromatic Degrading Bacterioplankton of the Baltic Sea

Abstract

Plasmids are mobile genetic elements that provide their hosts with many beneficial traits including in some cases the ability to degrade different aromatic compounds. To fulfill the knowledge gap regarding catabolic plasmids of the Baltic Sea water, a total of 209 biodegrading bacterial strains were isolated and screened for the presence of these mobile genetic elements. We found that both large and small plasmids are common in the cultivable Baltic Sea bacterioplankton and are particularly prevalent among bacterial genera Pseudomonas and Acinetobacter. Out of 61 plasmid-containing strains (29% of all isolates), 34 strains were found to carry large plasmids, which could be associated with the biodegradative capabilities of the host bacterial strains. Focusing on the diversity of IncP-9 plasmids, self-transmissible m-toluate (TOL) and salicylate (SAL) plasmids were detected. Sequencing the repA gene of IncP-9 carrying isolates revealed a high diversity within IncP-9 plasmid family, as well as extended the assumed bacterial host species range of the IncP-9 representatives. This study is the first insight into the genetic pool of the IncP-9 catabolic plasmids in the Baltic Sea bacterioplankton.

Strategy of Pseudomonas pseudoalcaligenes C70 for effective degradation of phenol and salicylate

“…The studied Pseudomonas pseudoalcaligenes strain C70 [ 24 , 25 ] (CELMS, University of Tartu, Estonia) and the other strains and plasmids are shown in S1 Table . Pure cultures were stored in 30% glycerol at -80°C.…”

“…In the Baltic Sea, bacterioplankton is influenced by coastal industries and marine traffic [ 23 ], both of which can cause pollution containing various compounds. We have shown previously that bacteria isolated from this environment possess IncP-9 family plasmids [ 24 ] and can degrade phenol, benzoate, m -toluate, salicylate, naphthalene [ 25 ] and toluene [ 26 ]. Vedler et al .…”

Polycyclic aromatic hydrocarbons in deep sea sediments: Microbe–pollutant interactions in a remote environment

“…The phylogenetic distribution of isolates includes the phyla Proteobacteria (α-, β-and γ-classes), Actinobacteria, Cyanobacteria, Bacteriodetes and Firmicutes. In addition to this, several genes encoding for PAH-degradation from different bacterial species share high homology thus suggesting that PAH catabolic genes are transferred horizontally -[horizontal gene transfer (HGT)] -acquired through conjugal transfer of plasmids (Anokhina et al, 2004;Coelho et al, 2011;Jutkina et al, 2011). Genetic information for PAH-degrading enzymes is often located in IncP plasmids, that are prone to broad range HGT and insertion in DNA sequences (Dennis, 2005).…”

Plasmid Detection, Characterization, and Ecology

“…These results strongly point to an enrichment of populations carrying IncP-1β plasmids that code for enzymes likely involved in the degradation of pesticides under field conditions. Other studies showed a high abundance of plasmids in different types of environments such as manure, manure-treated soils, river water sediments, and sea sediments by PCR Southern blot hybridization [17][18][19] or quantitative real-time PCR [20,21].…”