Bacterially self-assembled encapsulin nanocompartment for removing silver from water. (1st March 2021)

• Record Type: Journal Article
• Authors: Xing, Chong-Yang; Ma, Teng-Fei; Guo, Jin-Song; Shen, Yu; Yan, Peng; Fang, Fang; Chen, You-Peng
• Is Part Of: Water research. Volume 191(2021)
• Publication Date: 2021-03-01
• Subjects: Protein cage -- Self-assembly -- Bioremediation -- Silver -- Proteomics; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2020.116800
• Languages: English
• ISSNs: 0043-1354

Abstract

Highlights: Nanocompartments combine with silver in vitro . SPRi determine the agglomeration/dispersion of nanocompartments and silver. Use of model organism with nanocompartment for removal of silver. Nanocompartments up-regulate protein processing and secondary metabolites. Abstract: Compartmentalization can protect cells from the interference of external toxic substances by sequestering toxic products. We hypothesized that proteinaceous nanocompartments may be a feasible candidate material to be added to genetically modified bacteria for the sequestration of toxic environmental products, which would open up a new bioremediation pathway. Here, we showed that the model bacterium ( Escherichia coli ) with self-assembling nanocompartments can remove silver (Ag) from water. Transmission electron microscopy and energy dispersive X-ray (TEM-EDX) analysis showed that the nanocompartments combined stably with silver in vitro . In addition, when exposed to 30 μM AgNO3, the survival rate of genetically modified bacteria (with nanocompartments) was 86%, while it was just 59% in the wild-type bacteria (without nanocompartments). Label-free quantitative proteomics indicated that the nanocompartments enhanced bacterial activity by inducing the up-regulation of protein processing and secondary metabolites, and decreased their intracellular silver concentration, both of which contributed to their increased resistance to toxic silver. This study on nanocompartments has contributed to a deeper understanding of how bacteria respond to environmental stressors like heavy metal pollutants in water. The technology promises to provide a new strategy for recycling heavy metals from sewage. Graphical abstract: Image, graphical abstract