Enhanced Extracellular Synthesis of Gold Nanoparticles by Soluble Extracts from <i>Escherichia Coli</i> Transformed with <i>Rhizobium Tropici</i> Phytochelatin Synthase Gene

• Main Authors: Qunying Yuan, Manjula Bomma, Zhigang Xiao
• Format: Article
• Language: English
• Published: MDPI AG 2021-03-01
• Series: Metals
• Subjects: gold nanoparticles; extracellular nanoparticle synthesis; recombinant <i>Escherichia coli</i>; phytochelatin synthase; phytochelatins
• Online Access: https://www.mdpi.com/2075-4701/11/3/472

Phytochelatins, the enzymatic products of phytochelatin synthase, play a principal role in protecting the plants from heavy metal and metalloid toxicity due to their ability to scavenge metal ions. In the present study, we investigated the capacity of soluble intracellular extracts from <i>E. coli</i> cells expressing <i>R. tropici</i> phytochelatin synthase to synthesize gold nanoparticle. We discovered that the reaction mediated by soluble extracts from the recombinant <i>E. coli</i> cells had a higher yield of gold nanoparticles, compared to that from the control cells. The compositional and morphological properties of the gold nanoparticles synthesized by the intracellular extracts from recombinant cells and control cells were similar. In addition, this extracellular nanoparticle synthesis method produced purer gold nanoparticles, avoiding the isolation of nanoparticles from cellular debris when whole cells are used to synthesize nanoparticles. Our results suggested that phytochelatins can improve the efficiency of gold nanoparticle synthesis mediated by bacterial soluble intracellular extracts, and the potential of extracellular nanoparticle synthesis platform for the production of nanoparticles in large quantity and pure form is worth further investigation.