School of Resources and Environment, Northeast Agricultural University, Harbin 150030, PR China.
Laboratory of Environmental Microbiology and Toxicology, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong Special Administrative Region.
Bioresour Technol. 2020 Apr;302:122845. doi: 10.1016/j.biortech.2020.122845. Epub 2020 Jan 20.
Plasticizer dibutyl phthalate (DBP) pollution has received more and more attention. In this study, a DBP degrading bacteria Enterobacter sp. DNB-S2 was found to suffer membrane damage and oxidative stress during DBP degradation. Physiological and transcriptome analysis showed that 100 μmol L anthraquinone-2,6-disulfonate (AQDS) could enhance the ability of strain DNB-S2 for biodegradation of DBP. AQDS adjusted the cell surface structure, including increase levels of hydrophobic and unsaturated fatty acids. These changes increased the chemotactic ability of the strain DNB-S2 to the hydrophobic pollutant DBP and the fluidity of the cell membrane. The expression of methyl chemotactic protein and genes associated with cell membrane-fixed components were up-regulated. AQDS also improved the scavenging ability of ·OH and HO of DNB-S2 by promoting expression genes related to glutathione metabolism, thereby reducing oxidative stress. These results will provide new insights into the biodegradation of DBP.
增塑剂邻苯二甲酸二丁酯（DBP）污染受到了越来越多的关注。在这项研究中，发现一种能够降解 DBP 的细菌肠杆菌属 DNB-S2 在 DBP 降解过程中会遭受膜损伤和氧化应激。生理和转录组分析表明，100 μmol L 的蒽醌-2,6-二磺酸钠（AQDS）可以增强菌株 DNB-S2 对 DBP 的生物降解能力。AQDS 调整了细胞表面结构，包括增加了疏水性和不饱和脂肪酸的水平。这些变化提高了菌株 DNB-S2 对疏水性污染物 DBP 的趋化能力和细胞膜的流动性。甲基趋化蛋白和与细胞膜固定成分相关的基因的表达上调。AQDS 还通过促进与谷胱甘肽代谢相关的基因表达，提高了 DNB-S2 对·OH 和 HO 的清除能力，从而减轻了氧化应激。这些结果将为 DBP 的生物降解提供新的见解。
