Anaerobiosis favors biosynthesis of single and multi-element nanostructures

Abstract

Herein we report the use of an environmental multimetal(loid)-resistant strain, MF05, to biosynthesize single- or multi-element nanostructures under anaerobic conditions. Inorganic nanostructure synthesis typically requires methodologies and conditions that are harsh and environmentally hazardous. Thus, green/eco-friendly procedures are desirable, where the use of microorganisms and their extracts as bionanofactories is a reliable strategy. First, MF05 was entirely sequenced and identified as an Escherichia coli-related strain with some genetic differences from the traditional BW25113. Secondly, we compared the CdS nanostructure biosynthesis by whole-cell in a design defined minimal culture medium containing sulfite as the only sulfur source to obtain sulfide reduction from a low-cost chalcogen reactant. Under anaerobic conditions, this process was greatly favored, and irregular CdS (ex. 370 nm; em. 520–530 nm) was obtained. When other chalcogenites were tested (selenite and tellurite), only spherical Se0 and elongated Te0 nanostructures were observed by TEM and analyzed by SEM-EDX. In addition, enzymatic-mediated chalcogenite (sulfite, selenite, and tellurite) reduction was assessed by using MF05 crude extracts in anaerobiosis; similar results for nanostructures were obtained; however Se0 and Te0 formation were more regular in shape and cleaner (with less background). Finally, the in vitro nanostructure biosynthesis was assessed with salts of Ag, Au, Cd, and Li alone or in combination with chalcogenites. Several single or binary nanostructures were detected. Our results showed that MF05 is a versatile anaerobic bionanofactory for different types of inorganic NS. synthesis.

Minicells as an Escherichia coli mechanism for the accumulation and disposal of fluorescent cadmium sulphide nanoparticles

“…7 A). These color emission changes align with the classical kinetics of CdS nanoparticle biosynthesis, indicating nanoparticle growth, loss of the quantum confinement effect, and the formation of insoluble cadmium deposits [ 18 , 47 , 48 ]. In contrast, both mutant strains exhibit pellet fluorescence emission beginning after 8 h of biosynthesis.…”

Biosynthesis of Cu-In-S Nanoparticles by a Yeast Isolated from Union Glacier, Antarctica: A Platform for Enhanced Quantum Dot-Sensitized Solar Cells

“…This phenomenon is consistent with findings in other studies involving biological nanoparticles. The variation could be attributed to the diverse forms visualized by TEM (Figure 4) or the biological coating characteristic of biological nanoparticles, both of which influence the hydrodynamic size [79,80]. In summary, our characterization experiments lead us to conclude that, under biosynthesis conditions, the isolated F. stepposum strain synthesizes amorphous CIS nanoparticles capped with GSH.…”

“…This phenomenon is consistent with findings in other studies involving biological nanoparticles. The variation could be attributed to the diverse forms visualized by TEM ( Figure 4 ) or the biological coating characteristic of biological nanoparticles, both of which influence the hydrodynamic size [ 79 , 80 ].…”