Department of Microbiology, University of Silesia, Jagiellońska 28, 40-032 Katowice, Poland.
Ecotoxicol Environ Saf. 2019 Mar;169:615-622. doi: 10.1016/j.ecoenv.2018.11.081. Epub 2018 Nov 26.
The aim of the study was to assess the impact of inoculation of petroleum-contaminated soil with the hydrocarbon-degrading bacterial strains Rhodococcus erythropolis CD 130 and CD 167 or their consortium on the removal of hydrocarbons from the soil. Additionally, changes in the activity and structure of soil autochthonous bacterial communities were studied. At the end of the experiment, the fastest hydrocarbon removal was seen in the soil treated with the CD 167 strain (38.40%) and was statistically higher compared to the removal of total petroleum hydrocarbons (TPH) observed in soils inoculated with strain CD 130 (29.8%) or bacterial consortium CD 130 + CD 167 (29.72%). The rifampicin-resistant CD 130 and CD 167 strains, introduced as single strains or a consortium, survived in the soil for 42 days. The introduction of gram-positive strains of R. erythropolis primarily caused an increase in the biomass of branched phospholipid fatty acids (PLFAs), characteristic for gram-positive bacteria. Nevertheless, changes in the concentrations of gram-positive and gram-negative PLFA markers were periodic, and at the end of the experiment, significant changes were observed only in the case of the soil bioaugmented with the CD 167 strain. After the bioaugmentation, higher values of substrate-induced respiration (SIR) were observed in all the inoculated soils compared to the non-inoculated control. Nonetheless, after 91 days of incubation, a significant decrease in soil respiration was observed in the soil treated with single CD 130 or CD 167 strains or with their consortium. The number of transcripts of the CYP153 gene obtained on days 91 and 182 reflected the results of the hydrocarbon loss. The level of expression of the alkH gene in experimental soil was estimated and found to be higher than the level of expression of the CYP153 gene but did not coincide with the loss of hydrocarbons. The introduction of strains CD 130, CD 167, or CD 130 + CD 167 caused temporary changes in the composition of the soil autochthonous bacterial community, but it seems that these changes were needed for the enhanced removal of hydrocarbons from this soil.
本研究旨在评估接种石油降解细菌菌株红球菌（Rhodococcus erythropolis）CD130 和 CD167 或其混合物对土壤中烃类去除的影响。此外，还研究了土壤自生细菌群落结构和活性的变化。实验结束时，用 CD167 菌株处理的土壤中烃类去除速度最快（38.40%），与用 CD130 菌株（29.8%）或细菌混合物 CD130+CD167（29.72%）接种的土壤中观察到的总石油烃（TPH）去除相比，具有统计学上的显著差异。引入的耐利福平的 CD130 和 CD167 菌株作为单菌株或混合物在土壤中存活了 42 天。革兰氏阳性红球菌菌株的引入主要导致分支磷脂脂肪酸（PLFA）生物量增加，这是革兰氏阳性菌的特征。然而，革兰氏阳性和革兰氏阴性 PLFA 标记物浓度的变化是周期性的，实验结束时，仅在添加 CD167 菌株的土壤中观察到显著变化。生物强化后，与未接种对照相比，所有接种土壤的基质诱导呼吸（SIR）值均升高。然而，在培养 91 天后，单独添加 CD130 或 CD167 菌株或其混合物的土壤的土壤呼吸显著下降。在第 91 天和第 182 天获得的 CYP153 基因转录本数量反映了烃类损失的结果。实验土壤中 alkH 基因的表达水平估计高于 CYP153 基因的表达水平，但与烃类的损失不一致。CD130、CD167 或 CD130+CD167 菌株的引入导致土壤自生细菌群落组成发生暂时变化，但似乎这些变化是增强该土壤中烃类去除所必需的。
