Biogenic Control of Manganese Doping in Zinc Sulfide Nanomaterial Using Shewanella oneidensis MR-1

Abstract

Bacteria naturally alter the redox state of many compounds and perform atom-by-atom nanomaterial synthesis to create many inorganic materials. Recent advancements in synthetic biology have spurred interest in using biological systems to manufacture nanomaterials, implementing biological strategies to specify the nanomaterial characteristics such as size, shape, and optical properties. Here, we combine the natural synthetic capabilities of microbes with engineered genetic control circuits toward biogenically synthesized semiconductor nanomaterials. Using an engineered strain of Shewanella oneindensis with inducible expression of the cytochrome complex MtrCAB, we control the reduction of manganese (IV) oxide. Cytochrome expression levels were regulated using an inducer molecule, which enabled precise modulation of dopant incorporation into manganese doped zinc sulfide nanoparticles (Mn:ZnS). Thereby, a synthetic gene circuit controlled the optical properties of biogenic quantum dots. These biogenically assembled nanomaterials have similar physical and optoelectronic properties to chemically synthesized particles. Our results demonstrate the promise of implementing synthetic gene circuits for tunable control of nanomaterials made by biological systems.

Enhanced Light‐Driven Hydrogen Production by Self‐Photosensitized Biohybrid Systems

“…In the case of C. freundii mostly extracellular clusters of CdS nanoparticles were observed around of the cells (Figure 2 E/F). The CdS nanoparticles formed by S. oneidensis appeared as smaller spherical spots uniformly distributed on the cell surface (Figure 2 I/H), in agreement with previous studies [41, 42] . In the case of E. coli , small clusters of CdS particles were observed on the cell surface (Figure 2 K/L).…”

Enhanced Light‐Driven Hydrogen Production by Self‐Photosensitized Biohybrid Systems

“…TheC dS nanoparticles formed by S. oneidensis appeared as smaller spherical spots uniformly distributed on the cell surface (Figure 2I/H), in agreement with previous studies. [41,42] In the case of E. coli,s mall clusters of CdS particles were observed on the cell surface (Figure 2K/L). Theb iohybrid systems were further characterized by X-ray powder diffraction (XRD,F igure 3).…”

Bacterial extracellular electron transfer: a powerful route to the green biosynthesis of inorganic nanomaterials for multifunctional applications

“…Recently, Chellamuthu et al developed a genetic-control strategy to biosynthesize manganese-doped ZnS (Mn:ZnS) nanoparticles with different doping levels (Fig. 5 ) [ 155 ]. The authors found that the Mn doping level changed as a function of added inducer when the engineered strain of S. oneidensis with inducible expression of MtrCAB complex was used to control the reduction of Mn 4+ oxide.…”

“…5 Controlling manganese doping of ZnS quantum dots by engineered S. oneidensis JG3631 with the inducible expression of MtrCAB complex. a Chemically synthesized Mn doped ZnS NPs with varying optical properties, b the amount of the inducer (TMAO) regulating expression of MtrCAB complex that performs extracellular reduction, c relationship between Mn 2+ concentration and the addition of TMAO, d biogenic Mn doped ZnS quantum dots with varying optical properties as a function of Mn 2+ concentration [ 155 ]. …”