Polycyclic aromatic hydrocarbons (PAHs) enriching antibiotic resistance genes (ARGs) in the soils

Abstract

The prevalence of antibiotic resistance genes (ARGs) in modern environment raises an emerging global health concern. In this study, soil samples were collected from three sites in petrochemical plant that represented different pollution levels of polycyclic aromatic hydrocarbons (PAHs). Metagenomic profiling of these soils demonstrated that ARGs in the PAHs-contaminated soils were approximately 15 times more abundant than those in the less-contaminated ones, with Proteobacterial being the preponderant phylum. Resistance profile of ARGs in the PAHs-polluted soils was characterized by the dominance of efflux pump-encoding ARGs associated with aromatic antibiotics (e.g., fluoroquinolones and acriflavine) that accounted for more than 70% of the total ARGs, which was significantly different from representative sources of ARG pollution due to wide use of antibiotics. Most of ARGs enriched in the PAHs-contaminated soils were not carried by plasmids, indicating the low possibilities of them being transferred between bacteria. Significant correlation was observed between the total abundance of ARGs and that of Proteobacteria in the soils. Proteobacteria selected by PAHs led to simultaneously enriching of ARGs carried by them in the soils. Our results suggested that PAHs could serve as one of selective stresses for greatly enriching of ARGs in the human-impacted environment.

Antibiotics in the Soil Environment—Degradation and Their Impact on Microbial Activity and Diversity

“…Moreover, many microorganisms act as biological control agents by inhibiting the growth of pathogens (Varma and Buscot, 2005). The homeostasis of soil may be disturbed by biotic and abiotic factors, including bacteriophages, predation, competition, pesticide, heavy metals, toxic hydrocarbons, and antibiotics (Cycoń et al, 2011; Cycoń and Piotrowska-Seget, 2015, 2016; Sułowicz and Piotrowska-Seget, 2016; Xu et al, 2016; Chen et al, 2017; Wepking et al, 2017; Orlewska et al, 2018a). The high antimicrobial activity of antibiotics in soil should differentially inhibit the growth of soil microorganisms and thus influence the soil microbial community composition, which may result in alterations of the ecological functionality of the soil (Kotzerke et al, 2008; Keen and Patrick, 2013; Molaei et al, 2017) (Figure 3).…”

Can the legacy of industrial pollution influence antimicrobial resistance in estuarine sediments?

“…Due to difficulties in cultivating sediment micro-organisms (Great Plate Anomaly), it is currently unknown how many types of ARGs exist. However, the development of sequencing-based descriptive metagenomic approaches has provided the means to analyse the occurrence and abundance of previously unrecognised ARGs with examples of |successful applications (Li et al 2015a;Monier et al 2011;Chen et al 2017). The extent that environmental conditions impact antimicrobial resistance is becoming increasingly known.…”

“…Microbial degradation has an important role in the natural attenuation of PAHs in contaminated matrices (Van Dillewijn et al 2009); however, the presence of PAHs changes the community structure of indigenous bacteria with the number of hydrocarbon-degrading bacteria increases with increasing available hydrocarbons (De Menezes et al 2012;Zhang et al 2010;Maila et al 2005); it is difficult to understand which communities are present in historically contaminated sediments (Azarbad et al 2016;Singleton et al 2013). However, many PAH-tolerant bacterial isolates often exhibit strong resistance to metals and antibiotics (Ben Said et al 2008;Máthé et al 2012), and ARGs have been found in PAH-contaminated matrices (Chen et al 2017;Kang et al 2015).…”

“…PAHs have mutagenic properties (Liu et al 2017;Sun et al 2015), which could contribute towards AMR-either by directly changing DNA composition, or triggering stress/repair systems. There is little knowledge of specific mechanisms, but metagenomic profiling has demonstrated that PAH-contaminated soils with ARGs is in abundance approximately 15 times more than those less contaminated (Chen et al 2017).…”

Bacteria From the Multi-Contaminated Tinto River Estuary (SW, Spain) Show High Multi-Resistance to Antibiotics and Point to Paenibacillus spp. as Antibiotic-Resistance-Dissemination Players

“…Additionally, sublethal concentrations select resistant phenotypes from mutations or horizontal gene transfer (HGT) that sometimes use mobile genetic elements (MGEs) (Kohanski et al, 2010;Baharoglu and Mazel, 2011;Gutierrez et al, 2013;Haaber et al, 2017;Lekunberri et al, 2017). The AR in the environment is a natural process but is also promoted by anthropogenic pollutants like antibiotics, biocides, heavy metals, hydrocarbons, pesticides, and nanomaterials, among others (Baker-Austin et al, 2006;Dealtry et al, 2014;Pal et al, 2015Pal et al, , 2017Chen et al, 2017;Poole, 2017;Wang et al, 2018;Nguyen et al, 2019). Therefore, naturally antibiotic-resistant bacteria (ARB) could be a prime source for antibiotic resistance genes (ARGs) found in pathogens as certain findings may indicate (Rodríguez et al, 2004;Poirel et al, 2005Poirel et al, , 2012Yang J. et al, 2013;Jiang et al, 2017), but may later have evolved and be selected.…”