Distribution of Anaerobic Hydrocarbon-Degrading Bacteria in Soils from King George Island, Maritime Antarctica

Abstract

Anaerobic diesel fuel Arctic (DFA) degradation has already been demonstrated in Antarctic soils. However, studies comparing the distribution of anaerobic bacterial groups and of anaerobic hydrocarbon-degrading bacteria in Antarctic soils containing different concentrations of DFA are scarce. In this study, functional genes were used to study the diversity and distribution of anaerobic hydrocarbon-degrading bacteria (bamA, assA, and bssA) and of sulfate-reducing bacteria (SRB-apsR) in highly, intermediate, and non-DFA-contaminated soils collected during the summers of 2009, 2010, and 2011 from King George Island, Antarctica. Signatures of bamA genes were detected in all soils analyzed, whereas bssA and assA were found in only 4 of 10 soils. The concentration of DFA was the main factor influencing the distribution of bamA-containing bacteria and of SRB in the analyzed soils, as shown by PCR-DGGE results. bamA sequences related to genes previously described in Desulfuromonas, Lautropia, Magnetospirillum, Sulfuritalea, Rhodovolum, Rhodomicrobium, Azoarcus, Geobacter, Ramlibacter, and Gemmatimonas genera were dominant in King George Island soils. Although DFA modulated the distribution of bamA-hosting bacteria, DFA concentration was not related to bamA abundance in the soils studied here. This result suggests that King George Island soils show functional redundancy for aromatic hydrocarbon degradation. The results obtained in this study support the hypothesis that specialized anaerobic hydrocarbon-degrading bacteria have been selected by hydrocarbon concentrations present in King George Island soils.

Hydrocarbon degradation test among the microbial community in oil-contaminated soil of power generators in Kerbala city, Iraq

“…The current study demonstrated that the microbial community was detected through the oil-contaminated and non-oil-contaminated soils, where their numbers were observed in the stations at levels of log 5.3 -6.4 CFU g -1 . Several prior publications have investigated the microbial community in the different areas of oil-contaminated and nonoil-contaminated soils by means of both conventional and molecular methods [14,15,16]. In agreement with the current results, data obtained from the study of Wolińska et al ., showed that the numbers of cultivable bacteria which could be isolated from contaminated and control samples were different but no significant differences were found [14].…”

Metagenomic analysis of microbial communities across a transect from low to highly hydrocarbon‐contaminated soils in King George Island, Maritime Antarctica

“…While the nitrate produced could potentially be converted to ammonium through assimilatory nitrate reduction, we instead found genetic evidence for its use as an electron acceptor for anaerobic respiration through denitrification, which would result in loss of N from the system (Figure 5b). The potential role of denitrifiers in the degradation of aromatic hydrocarbons in Antarctic soils has also been proposed by Sampaio et al (2017).…”

Methane Oxidation Coupled to Selenate Reduction in a Membrane Bioreactor under Oxygen-Limiting Conditions

“…Along with type-II Methylocystis, the type-I methanotroph Methylococcus (3.2%) and unclassified Methylococcaceae (6.5%) were also detected in the bioreactor, suggesting their potential roles for methane oxidation . In addition to aerobic methanotrophs, two recognized denitrifying bacteria Acidovorax and Lautropia were detected, accounting for 4.1 and 2.9% of the total microbial sequences, respectively. Additionally, unclassified members of Rhodocyclaceae were also enriched, with relative abundance increasing from 0.1% in the inoculum to 5.7% on day 360.…”