Silva-Portela Rita de Cássia Barreto, Minnicelli Carolina Fonseca, Freitas Júlia Firme, Fonseca Marbella Maria Bernardes, Lima Silva Douglas Felipe de, Silva-Barbalho Kamila Karla, Falcão Raul Maia, Bruce Thiago, Cavalcante João Vitor Ferreira, Dalmolin Rodrigo Juliani Siqueira, Agnez-Lima Lucymara Fassarella
Department of Cell Biology and Genetics, Federal University of Rio Grande do Norte, Natal 59078900, Brazil.
Bioinformatics Multidisciplinary Environment - IMD, Federal University of Rio Grande do Norte, Natal 59078900, Brazil.
J Hazard Mater. 2025 Mar 5;485:136866. doi: 10.1016/j.jhazmat.2024.136866. Epub 2024 Dec 16.
This study investigates the transcriptional profile of a novel oil-degrading microbial consortium (MC1) composed of four bacterial isolates from Brazilian oil reservoirs: Acinetobacter baumannii subsp. oleum ficedula, Bacillus velezensis, Enterobacter asburiae, and Klebsiella pneumoniae. Genomic analysis revealed an enrichment of genes associated with xenobiotic degradation, particularly for aminobenzoate, atrazine, and aromatic compounds, compared to reference genomes. The consortium demonstrated superior growth and complete oil degradation relative to individual strains. Transcriptional profiling during growth on oil indicated that key subsystems involved membrane transport, stress response, and dehydrogenase complexes, crucial for hydrocarbon uptake. Notably, genes for degrading aromatics, naphthalene, and chloroalkanes were significantly expressed during the initial oil growth phase. The dominant gene expressed was alkane 1-monooxygenase, particularly in the late growth phase. While A. baumannii exhibited the highest transcriptional activity, B. velezensis showed lower activity despite possessing numerous hydrocarbon degradation genes. The synergistic interactions among strains, confirmed by complementary gene expression patterns, position MC1 as a promising bioremediation agent for hydrocarbon-contaminated environments. However, more than collaboration, competition for nutrient uptake and resistance to stress drive gene expression and adaptation in the presence of oil as the carbon source.
本研究调查了一种新型石油降解微生物群落（MC1）的转录谱，该群落由从巴西油藏分离出的四种细菌组成：鲍曼不动杆菌油亚种菲塞杜拉、贝莱斯芽孢杆菌、阿氏肠杆菌和肺炎克雷伯菌。基因组分析显示，与参考基因组相比，该群落中与异生素降解相关的基因有所富集，尤其是与氨基苯甲酸、阿特拉津和芳香化合物降解相关的基因。与单个菌株相比，该群落表现出更好的生长和完全的石油降解能力。在以石油为生长底物时的转录谱分析表明，关键子系统涉及膜转运、应激反应和脱氢酶复合物，这些对于碳氢化合物的摄取至关重要。值得注意的是，在石油生长初期，降解芳烃、萘和氯代烷烃的基因显著表达。表达量最高的基因是烷烃1-单加氧酶，尤其是在生长后期。虽然鲍曼不动杆菌表现出最高的转录活性，但贝莱斯芽孢杆菌尽管拥有众多碳氢化合物降解基因，其活性却较低。菌株间的协同相互作用通过互补的基因表达模式得到证实，这使得MC1成为受碳氢化合物污染环境中有前景的生物修复剂。然而，除了合作之外，在以石油作为碳源的情况下，对营养物质摄取的竞争和对压力的抗性驱动着基因表达和适应性。
