Insights into the role of extracellular DNA in heavy metal adsorption

被引：23

作者：

Peng, Tangjian ^{[1
,2
]}

Liao, Wanqing ^{[2
]}

Gu, Guohua ^{[2
]}

Qiu, Guanzhou ^{[2
]}

Wu, Xueling ^{[2
]}

Yang, Fei ^{[1
,4
]}

Zeng, Weimin ^{[2
,3
]}

机构：

[1] Univ South China, Sch Publ Hlth, Hunan Prov Key Lab Typ Environm Pollut & Hlth Haz, Hengyang 421001, Peoples R China

[2] Cent South Univ, Sch Minerals Proc & Bioengn, Changsha 410083, Peoples R China

[3] CSIRO Proc Sci & Engn, Clayton, Vic 3168, Australia

[4] Cent South Univ, Xiangya Sch Publ Hlth, Hunan Prov Key Lab Clin Epidemiol, Changsha 410078, Peoples R China

来源：

SCIENCE OF THE TOTAL ENVIRONMENT | 2022年 / 808卷

基金：

中国国家自然科学基金; 中国博士后科学基金; 芬兰科学院;

关键词：

eDNA; EPS; Heavy metal; Adsorption; Functional groups; POLYMERIC SUBSTANCES EPS; BIOSORPTION PROPERTIES; PSEUDOMONAS-PUTIDA; BINDING; CD; RESISTANCE; CADMIUM; RELEASE; ABILITY; ZN(II);

D O I：

10.1016/j.scitotenv.2021.152067

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

Extracellular polymeric substances (EPS) participate in heavy metal adsorption in the aquatic environments. Extracellular DNA (eDNA) is an essential component of EPS, but its involvement in metal binding remains ambiguous. Herein, the role of eDNA in Cd(II) and Ni(II) adsorption was described using a combination of semi-quantitative and qualitative approaches. EPS were extracted from Burkholderia sp. MBR-1 and eDNA accounted for 6.9% of the total mass of EPS. The eDNA in the extracted EPS was digested using the DNase II to prepare an eDNA-free EPS sample. Potentiometric titration unveiled that the number of total binding sites of the eDNA-free EPS was 19% lower than the untreated EPS. The Cd(II) and Ni(II) adsorption capacity of the eDNA-free EPS was lower than the untreated EPS at the pH range of 4-7. At pH 7, the results of batch adsorption experiments showed that removing eDNA from EPS resulted in declines of 12.6% and 15.7% in the adsorption capacities for Cd(II) and Ni(II), respectively. Furthermore, Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy unraveled that the phosphoryl groups and purines of eDNA are responsible for Cd(II) and Ni(II) complexation. The results demonstrated that eDNA plays an essential role in heavy metal adsorption.

引用

页数：7

共 46 条

[1] Fabrication, characterization and U(VI) sorption properties of a novel biochar derived from Tribulus terrestris via two different approaches [J].