Microbial tellurite reduction and production of elemental tellurium nanoparticles by novel bacteria isolated from wastewater

Two highly tellurite-resistant bacteria were isolated from wastewater. Both bacteria could perform tellurite reduction under an initial pH of 5–9, temperature of 20–37 °C, and salinity conditions lower than 5%. The maximum reduction rate of strain WYA (Vmax = 20.45 μMh−1) was much higher than that of strain WYS (Vmax = 11.49 μMh−1). Both bacteria produced tellurium nanorods that were accumulated intracellularly or extracellularly. Strain WYA is a new strain belonging to the Raoultella genus, whereas strain WYS belongs to the Escherichia genus. This study indicated that both these bacteria are potential microorganisms for green synthesis of tellurium nanorods, which have a wide application in environmental remediation and the nanotechnology industry.