Novel hydrocarbonoclastic metal-tolerant Acinetobacter and Pseudomonas strains from Aconcagua river oil-polluted soil

Abstract

Bioremediation of sites polluted with petroleum hydrocarbons and heavy metals is a major challenge. The aim of this study was the isolation and characterization of hydrocarbon-degrading and heavy metal-tolerant bacteria. Sixteen hydrocarbonoclastic bacteria were isolated by enrichment from a crude oil-contaminated soil at Aconcagua river mouth, Central Chile. Most strains were cocci-shaped and exhibited circular cream-colored colonies with smooth texture. Isolates were resistant to bacitracin and penicillin, and two isolates were motile.Isolates were identified by 16S rRNA and rpoD and rpoB genes sequence analyses. Most isolates belonged to Gammaproteobacteria including Acinetobacter radioresistens (4 isolates), Acinetobacter calcoaceticus (1), Pseudomonas stutzeri (2) and Pseudomonas chloritidismutans (1). Seven isolates possessed 97% 16S rRNA gene similarity with A. calcoaceticus ATCC 23055T, suggesting that these probably represent a new Acinetobacter species. One isolate is an Actinobacteria of the Kocuria genus. All isolates were able to grow on crude oil, whereas eleven Acinetobacter and Pseudomonas strains grew on n-hexadecane. Pseudomonas isolates grew on fluorene (DM88 and DM95) and naphthalene (DD74). Acinetobacter isolates grew on fluorene (DD75, DD79 and DM81) and phenanthrene (DM82). Remarkably, most isolates (except DD79) exhibited copper or cadmium tolerance. These novel hydrocarbonoclastic and heavy metal-tolerant Pseudomonas and Acinetobacter strains are potential biocatalysts for bioremediation.

A newly isolated strain of Serratia sp. from an oil spillage site of Assam shows excellent bioremediation potential

“…Fossil oil contamination in terrestrial and water body largely hampers the ecosystem by increasing the toxicity level in the environment and is considered as a serious issue of global concern (Gordon et al 2018;Méndez et al 2017). Oil spillage may take place due to a number of reasons including onshore or offshore oil exploration practices, oil disposal practices, human negligence, and accidents during transportation of oil, natural calamities or may be due to intentional release of oil during wars (Chen et al 2018;Gong et al 2014).…”

“…are largely explored for their potential to degrade hydrocarbon but least explored for their in situ or ex situ potential (Mukherjee and Bordoloi 2011;Sangeetha and Thangadurai 2014;Yenn et al 2014;Guermouche et al 2015;Patowary et al 2018;Ramadass et al 2018), whereas we report the potential application of Serratia nematodiphila for such studies for the very first time. However, petroleumcontaminated sites also serve as a potential source of novel indigenous hydrocarbon-degrading microorganisms (Chaudhary and Kim 2017;Méndez et al 2017). Considering the above facts, a study was carried out for the exploitation of novel indigenous hydrocarbon-degrading microorganisms from a petroleum oil spillage site located in Rudrasagar area (26.11°N, 91.83°E) of Assam, Northeast India.…”

Genomic and Physiological Traits of the Marine Bacterium Alcaligenes aquatilis QD168 Isolated From Quintero Bay, Central Chile, Reveal a Robust Adaptive Response to Environmental Stressors

“…Isolation and characterization of multistress-tolerant bacteria from severe environments, lead to potential discovery of novel strains for the clean-up of polluted sites (Head et al, 2006; Fuentes et al, 2014; Orellana et al, 2018). Diverse bacteria, including extremophiles, have been used as biocatalysts for bioremediation of soils and water contaminated with persistent organic pollutants and heavy metals (Harayama et al, 2004; Saavedra et al, 2010; Rojas et al, 2011; Fuentes et al, 2016; Méndez et al, 2017; Orellana et al, 2018).…”

Sequestration Specificity of Single or Co-existing Benzene, 1,3,5-Trimethylbenzene, and Naphthalene in Soil

“…Soil pollution by fertilizers (da Silva et al 2017), heavy metals (Cornejo et al 2017), and organic pollutants (U.S. EPA 2014; Rosell-Melé et al 2017) has received much attention worldwide. Petroleum hydrocarbons, from the production, transportation, storage, and distribution of fuels, can affect soil ecosystems and result in significant deterioration of soil quality (Dindar et al 2017;Mendez et al 2017). The long-term contact of petroleum hydrocarbons with soil often leads to progressive immobilization or sequestration of compounds within contaminated soil; in addition, the bioavailability of contaminants will decrease the longer they remain in soil (Li et al 2016;Galitskaya et al 2016).…”

“…Organic mixtures such as petroleum hydrocarbons are the most frequently found non-aqueousphase liquids (LNAPLs) in the environment. The presence of NAPLs in sub-surfaces poses a serious threat to groundwater, as they can act as long-term sources of highly toxic substances and can reduce the ability of bioremediation (Dindar et al 2017;Mendez et al 2017;Varjani et al 2017). The degradation of NAPLs is closely related to their sequestration, dissolution, and biodegradation in sub-surfaces over time (Barros et al 2013;Dindar et al 2017).…”