Isolation and Characterization of Phenanthrene Degrading Bacteria from Diesel Fuel-Contaminated Antarctic Soils

Abstract

Antarctica is an attractive target for human exploration and scientific investigation, however the negative effects of human activity on this continent are long lasting and can have serious consequences on the native ecosystem. Various areas of Antarctica have been contaminated with diesel fuel, which contains harmful compounds such as heavy metals and polycyclic aromatic hydrocarbons (PAH). Bioremediation of PAHs by the activity of microorganisms is an ecological, economical, and safe decontamination approach. Since the introduction of foreign organisms into the Antarctica is prohibited, it is key to discover native bacteria that can be used for diesel bioremediation. By following the degradation of the PAH phenanthrene, we isolated 53 PAH metabolizing bacteria from diesel contaminated Antarctic soil samples, with three of these isolates exhibiting a high phenanthrene degrading capacity. In particular, the Sphingobium xenophagum D43FB isolate showed the highest phenanthrene degradation ability, generating up to 95% degradation of initial phenanthrene. D43FB can also degrade phenanthrene in the presence of its usual co-pollutant, the heavy metal cadmium, and showed the ability to grow using diesel-fuel as a sole carbon source. Microtiter plate assays and SEM analysis revealed that S. xenophagum D43FB exhibits the ability to form biofilms and can directly adhere to phenanthrene crystals. Genome sequencing analysis also revealed the presence of several genes involved in PAH degradation and heavy metal resistance in the D43FB genome. Altogether, these results demonstrate that S. xenophagum D43FB shows promising potential for its application in the bioremediation of diesel fuel contaminated-Antarctic ecosystems.

Effects of heavy metals on diesel metabolism of psychrotolerant strains of Arthrobacter sp. from Antarctica

“…strain Vi 1, respectively. The results of this study is also in agreement with Gran-Scheuch et al (2017) who, reported that isolated bacterial strain Sphingobium xenophagum D43FB was capable of degrading phenanthrene in the presence of heavy metals present in diesel.…”

Insight Into Metabolic Versatility of an Aromatic Compounds-Degrading Arthrobacter sp. YC-RL1

“…As one of the most common structural units of organic compounds in nature, the benzene ring and its derivatives are extensively used in industrial production, including daily supplies, agro-products, energy products, etc. Although some structural properties of these compounds make them recalcitrant to degradation, many aromatic-degrading microbes have been isolated ( Fuchs et al, 2011 ; Xu et al, 2015 ), with metabolic pathways and mechanisms reported for some ( Chauhan et al, 2000 ; Zhang et al, 2012 ; Shah et al, 2014 ; Gran-Scheuch et al, 2017 ), but not all ( Goncalves et al, 2006 ; Zhou et al, 2015 ). These works and hundreds of others have advanced our knowledge of aromatic compounds degradation.…”

Bacterial chemotaxis: a way forward to aromatic compounds biodegradation

“…However, biodegradation of PAHs is gaining much attention due to the extravagant cost of the aforementioned conventional methods and environmental concerns. Therefore, literature also furnishes much information from original research articles [132,133] to review articles [10,134] on PAHs biodegradation. Scopus, a well-recognized database for scientific literature search, generated 406 entries for keywords "naphthalene and biodegradation", accessed on 15/11/2019.…”