Microbial Reduction of Metal-Organic Frameworks Enables Synergistic Chromium Removal

Abstract

9Microbial interactions with redox-active materials are ubiquitous in geochemical cycling and 10 bioelectrochemical devices, but the biotic-abiotic interface has proven challenging to study due to 11 the structural complexity of mineral substrates. In contrast, metal-organic frameworks are a class Cr(VI) adsorption capacity, demonstrating that the framework confers protection to the bacteria 22 and that no regenerative step is needed for continued bioremediation. In sum, our results show 23 that the study of microbial-material interactions can be extended to metal-organic frameworks and 24 suggest that these materials may offer a promising alternative to metal oxides in applications 25 seeking to combine the advantages of bacterial metabolism and synthetic materials.

Tailored extracellular electron transfer pathways enhance the electroactivity of Escherichia coli

“…External energy input can be used as a driving force for anabolic reactions [1,2] . In contrast, catabolic reactions enable bioelectricity generation from organic substrates [3] , reductive extracellular synthesis of products such as nanoparticles [4,5] and polymers [6] , as well as degradation of pollutants for bioremediation purposes [7] . In addition, quantification of the electron transfer can be exploited in biosensing applications [8,9] .…”

Extracellular Electron Transfer Enables Cellular Control of Cu(I)-catalyzed Alkyne-Azide Cycloaddition

“…electroactive bacterium Shewanella oneidensis (wild-type MR-1) is regulated through a set of well-defined heme-containing cytochromes in the Mtr-pathway (metal-reducing pathway) [15][16][17] . This pathway allows S. oneidensis to use oxidized metal ions, including organometallic catalysts, as terminal electron acceptors under anaerobic conditions [18][19][20] . Indeed, bacterial reduction of metals including iron(III) and copper(II) by E. coli and S. oneidensis have previously been used to perform atom-transfer radical polymerization (ATRP) [21][22][23] , and transcriptional regulation of specific EET proteins in S. oneidensis has enabled dynamic control over metal reduction and resulting catalysis [24][25] .…”