Lenchi Nesrine, Ahmedi Wissam Nour El Houda, Llirós Marc
Department of Natural and Life Sciences, Faculty of Sciences, University Algiers 1 BenYoucef Benkhedda, Algiers, Algeria.
Bioinformatics, Applied Microbiology and Biomolecules Laboratory, Faculty of Sciences, University of M'Hamed Bougara of Boumerdès, Boumerdes, Algeria.
Int Microbiol. 2024 Apr;27(2):615-630. doi: 10.1007/s10123-023-00419-0. Epub 2023 Aug 15.
Investigating the ability of bacteria to simultaneously enhance hydrocarbon removal and reduce heavy metals' toxicity is necessary to design more effective bioremediation strategies. A bacterium (NL2 strain) isolated from an Algerian oilfield was cultivated on crude oil as sole carbon and energy sources. Molecular analyses of the 16S rRNA gene sequence placed the strain within the Cutibacterium genera. This isolate was able to tolerate up to 60% of crude oil as sole carbon source. Chemical analyses (GC-MS) evidenced that strain NL2 was able to degrade 92.22% of crude oil (at optimal growing conditions: pH 10, 44 °C, 50 g L NaCl, and 20% of crude oil (v/v) as sole carbon source) in only 7 days. NL2 isolate was also able to produce biosurfactants with reduction of surface tension of growing media (29.4 mN m). On the other hand, NL2 strain was able to tolerate high lead (Pb) and copper (Cu) concentrations (up to 60 mM). In fact, NL2 cultivated in the presence of 20% of crude oil, and 0.48 mM of Pb was able to reduce Pb concentration by a 41.36%. In turn, when cultivated on high Pb concentration (15 mM), the strain was able to remove 35.19% of it and 86.25% of crude oil, both in a time frame of 7 days. Our findings suggest that Cutibacterium strain NL2 is able to efficiently use and remove a wide range of crude oil substrates in presence of high Pb concentration. Accordingly, NL2 strain is of extreme interest from a biotechnological standpoint.
研究细菌同时增强碳氢化合物去除能力和降低重金属毒性的能力，对于设计更有效的生物修复策略至关重要。从阿尔及利亚油田分离出的一种细菌（NL2菌株），以原油作为唯一碳源和能源进行培养。对16S rRNA基因序列的分子分析将该菌株归为棒状杆菌属。该分离株能够耐受高达60%的原油作为唯一碳源。化学分析（GC-MS）表明，NL2菌株在仅7天内就能降解92.22%的原油（在最佳生长条件下：pH值为10、44°C、50 g/L NaCl以及20%的原油（v/v）作为唯一碳源）。NL2分离株还能够产生生物表面活性剂，降低生长培养基的表面张力（29.4 mN/m）。另一方面，NL2菌株能够耐受高浓度的铅（Pb）和铜（Cu）（高达60 mM）。事实上，在含有20%原油和0.48 mM Pb的条件下培养的NL2能够将Pb浓度降低41.36%。反过来，当在高Pb浓度（15 mM）下培养时，该菌株在7天的时间内能够去除35.19%的Pb和86.25%的原油。我们的研究结果表明，棒状杆菌属NL2菌株在高Pb浓度下能够有效利用和去除多种原油底物。因此，从生物技术角度来看，NL2菌株极具研究价值。
