Regional University Centre of Excellence in Environmental Industry, Szent István University, Páter K. u. 1, Gödöllő, H-2100, Hungary.
Department of Environmental Safety and Ecotoxicology, Szent István University, Páter K. u. 1, Gödöllő, H-2100, Hungary.
Environ Sci Pollut Res Int. 2018 Nov;25(32):32178-32195. doi: 10.1007/s11356-018-3096-6. Epub 2018 Sep 15.
Due to their high resistance against environmental challenges, bacterial biofilms are ubiquitous and are frequently associated with undesired phenomena in environmental industry (e. g. biofouling). However, because of the high phylogenetic and functional diversity, bacterial biofilms are important sources of biotechnologically relevant microorganisms, e.g. those showing bioremediation potential. In our previous work, the high phylogenetic and metabolic diversity of a clogging biofilm, developed in a simple aromatic hydrocarbon (BTEX)-contaminated groundwater well was uncovered. The determination of relationships between different groups of biofilm bacteria and certain metabolic traits has been omitted so far. Therefore, by setting up new biofilm-based enrichment microcosms, the research goal of the present study was to identify the aerobic/hypoxic BTEX-degrading and/or prolific biofilm-forming bacteria. The initial bacterial community composition as well as temporal dynamics due to the selective enrichment has been determined. The obtained results indicated that the concentration of dissolved oxygen may be a strong selective force on the evolution and final structure of microbial communities, developed in hydrocarbon-contaminated environments. Accordingly, members of the genus Malikia proved to be the most dominant community members of the aerobic BTEX-degrading enrichments. Acidovorax spp. dominated the oxygen-limited/hypoxic setup. During the study, a strain collection of 23 different bacterial species was obtained. Non-pathogenic members of this strain collection, with outstanding biodegradation (e.g. Pseudomonas, Variovorax isolates) and biofilm-forming potential (e.g. Rhizobium), may potentially be applied in the development of biofilm-based semipermeable reactive biobarriers.
由于其对环境挑战的高度抗性，细菌生物膜无处不在，并且经常与环境工业中的不良现象（例如生物污垢）相关联。然而，由于其高度的系统发育和功能多样性，细菌生物膜是生物技术相关微生物的重要来源，例如那些具有生物修复潜力的微生物。在我们之前的工作中，揭示了在简单芳香烃（BTEX）污染的地下水中形成的堵塞生物膜的高度系统发育和代谢多样性。到目前为止，尚未确定生物膜细菌不同群体之间的关系与某些代谢特征之间的关系。因此，通过建立新的基于生物膜的富集微宇宙，本研究的研究目标是确定好氧/缺氧 BTEX 降解和/或高产生物膜形成细菌。确定了初始细菌群落组成以及由于选择性富集而导致的时间动态。获得的结果表明，溶解氧的浓度可能是烃污染环境中微生物群落进化和最终结构的一个强有力的选择力。因此，Malikia 属的成员被证明是好氧 BTEX 降解富集物中最主要的群落成员。在氧气有限/缺氧设置中，Acidovorax spp.占主导地位。在研究过程中，获得了 23 种不同细菌物种的菌株收集。该菌株收集的非致病性成员，具有出色的生物降解（例如假单胞菌，Variovorax 分离株）和生物膜形成潜力（例如根瘤菌），可能潜在地应用于生物膜基半渗透反应生物阻隔层的开发。
