title: A study on the dynamics of the zraP gene expression profile and its application to the construction of zinc adsorption bacteria.
abstract: Zinc ion plays essential roles in biological chemistry. Bacteria acquire Zn(2+) from the environment, and cellular concentration levels are controlled by zinc homeostasis systems. In comparison with other homeostatic systems, the ZraSR two-component system was found to be more efficient in responding to exogenous zinc concentrations. To understand the dynamic response of the bacterium ZraSR two-component system with respect to exogenous zinc concentrations, the genetic circuit of the ZraSR system was integrated with a reporter protein. This study was helpful in the construction of an E. coli system that can display selective metal binding peptides on the surface of the cell in response to exogenous zinc. The engineered bacterial system for monitoring exogenous zinc was successfully employed to detect levels of zinc as low as 0.001 mM, which directly activates the expression of chimeric ompC(t)--zinc binding peptide gene to remove zinc by adsorbing a maximum of 163.6 μmol of zinc per gram of dry cell weight. These results indicate that the engineered bacterial strain developed in the present study can sense the specific heavy metal and activates a cell surface display system that acts to remove the metal.
authors.affiliation: School of Chemical Engineering and Bioengineering, University of Ulsan, Daehakro 93, Nam-gu, Ulsan, 680-749, Republic of Korea.
authors.forename: Sambandam
authors.initials: S
authors.lastname: Ravikumar
authors.forename: Ik-keun
authors.initials: IK
authors.lastname: Yoo
authors.forename: Sang Yup
authors.initials: SY
authors.lastname: Lee
authors.forename: Soon Ho
authors.initials: SH
authors.lastname: Hong
mesh_terms: D000327:Adsorption; D001673:Biodegradation, Environmental; D017931:DNA Primers / Q000235:genetics; D004926:Escherichia coli / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial; D005818:Genetic Engineering / Q000379:methods; D005838:Genotype; D007477:Ions; D008670:Metals / Q000737:chemistry; D008954:Models, Biological; D008957:Models, Genetic; D010455:Peptides / Q000737:chemistry; D010957:Plasmids / Q000378:metabolism; D013997:Time Factors; D015032:Zinc / Q000737:chemistry*
chemical_list: D017931:DNA Primers; D029968:Escherichia coli Proteins; D007477:Ions; D008670:Metals; D010455:Peptides; C114106:zraP protein, E coli; D015032:Zinc