A Biological Production of ZnS (Sphalerite) Nanoparticles with Desulfovibrio gigas

Sulfur-/sulfate-reducing bacteria (SRB) have been used for remediation of metalcontaminated ground water and soil through the precipitation of metal sulfides. These metal sulfides range from 3 nm to 3 μm in diameter. Of specific interest to this research are zinc sulfide nanoparticles (ZnS NPs) produced by SRBs with a diameter of ~3 nm. These ZnS NPs can be used as catalysts to grow nano-wires, and these nano-wires, coupled with green fluorescent protein (GFP), might be used to make a cost-efficient biosensor. Currently, there is no report of a pure culture that produces ZnS NPs; therefore, this study investigates the ability of a pure culture of Desulfovibrio gigas in two different media (Media 63 and Media 149) to produce ZnS NPs as a metal precipitate. This study shows that both media are able to grow D. gigas in the absence of zinc in the solution. D. gigas growth in media containing zinc could not be determined due to ZnOH precipitates.