Specific Adsorption of Silver (I) from the Aqueous Phase by <i>Saccharomyces cerevisiae</i> Cells with Enhanced Displaying CueR Protein

Abstract

Three types of CueR proteins were anchored on the surface of Saccharomyces cerevisiae cells via surface display technology. The surface-engineered cells showed enhanced adsorption capacity and specificity toward Ag (I) in aqueous phase than control groups. A series of experiments were conducted to investigate the resistance of the surface-engineered cells toward environmental changes including pH, temperature, and eluent. The surface-engineered Saccharomyces cerevisiae cells had the highest adsorption capacity of 2.799 mg/g, which was 87.3% higher than original cells. The engineered cells were able to tolerate an acidic environment (pH=3.0 to 5.0) and high temperature (up to 50°C) with relatively stable adsorption performance. Desorption efficiency was 11% (pH=5.0, 1&nbsp;mM eluent), which implied the absorbed Ag (I) ions bonded to the cells with high affinity.