Selective Lead Adsorption by Recombinant Escherichia coli Displaying a Lead-Binding Peptide

• Published in: Applied biochemistry and biotechnology 2013-02, Vol.169 (4), p.1188-1196
• Main Authors: Nguyen, Thuong T. L., Lee, Hae Ryong, Hong, Soon Ho, Jang, Ji-Ryang, Choe, Woo-Seok, Yoo, Ik-Keun
• Format: Article
• Language: English
• Subjects: Adsorption; Biochemistry; Biological and medical sciences; Biotechnology; Chemistry; Chemistry and Materials Science; Cobalt - metabolism; Copper - metabolism; E coli; Escherichia coli; Escherichia coli - metabolism; Fundamental and applied biological sciences. Psychology; Isotherms; Lead; Lead - metabolism; Metal ions; Nickel - metabolism; Peptides; Peptides - metabolism
• ISSN: 0273-2289; 1559-0291
• DOI: 10.1007/s12010-012-0073-2

A highly specific lead-binding peptide ThrAsnThrLeuSerAsnAsn was displayed on Escherichia coli , and lead adsorption characteristics of the recombinant bacteria were investigated. Cell surface-displayed peptide was expressed under the control of an arabinose promoter using outer membrane protein C (OmpC t ) as an anchoring motif. The optimal induction period and arabinose concentration for the expression of peptide-fused OmpC t were determined to be 2 h and 0.001 g/L, respectively. Selective adsorption of Pb 2+ onto recombinant cells was verified with individual or combinatory use of four metal ions, Pb 2+ , Ni 2+ , Co 2+ , and Cu 2+ ; the amount of bound Pb 2+ onto the biosorbents was significantly higher than the other metal ions. The adsorption isotherm of recombinant cells for Pb 2+ followed the Langmuir isotherm with a maximum adsorption loading ( q max ) of 526 μmol/g dry cell weight.