title: Fluorescence-based sensing system for copper using genetically engineered living yeast cells.
abstract: A whole cell-based optical sensing system for copper was developed based on Saccharomyces cerevisiae cells harboring plasmid pYEX-GFPuv. The basis of this system was the ability of the transcriptional activator protein Ace1 present in S. cerevisiae to control the expression of the reporter protein, GFPuv. When copper ions are present in the sample, the Ace1 protein activates the cup1 promoter located upstream from the gfpuv gene in plasmid pYEX-GFPuv, thus inducing the production of GFPuv. The concentration of copper ions in the sample can then be related to the GFPuv expressed in the yeast. The amount of GFPuv produced in the system was determined by monitoring the fluorescence emitted at 507 nm after excitation at 397 nm. This system can detect copper at concentrations as low as 5 x 10(-7) M, and is selective for copper over a variety of metal ions, with the exception of silver. The applicability of this sensing system to different analytical platforms and in real samples is demonstrated.
authors.affiliation: Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055, USA.
authors.forename: Ranjit S
authors.initials: RS
authors.lastname: Shetty
authors.forename: Sapna K
authors.initials: SK
authors.lastname: Deo
authors.forename: Yue
authors.initials: Y
authors.lastname: Liu
authors.forename: Sylvia
authors.initials: S
authors.lastname: Daunert
mesh_terms: D001681:Biological Assay / Q000379:methods*; D015374:Biosensing Techniques / Q000379:methods*; D002352:Carrier Proteins; D003300:Copper / Q000032:analysis* / Q000494:pharmacology*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004784:Environmental Monitoring / Q000379:methods; D004785:Environmental Pollutants / Q000032:analysis; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D008668:Metallothionein / Q000235:genetics / Q000378:metabolism; D015202:Protein Engineering / Q000379:methods; D011994:Recombinant Proteins / Q000032:analysis / Q000378:metabolism; D012440:Saccharomyces / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism; D013050:Spectrometry, Fluorescence / Q000379:methods*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: C500769:CUP1-1 protein, S cerevisiae; C060256:CUP2 protein, S cerevisiae; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D004785:Environmental Pollutants; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; C007121:copper thionein; D049452:Green Fluorescent Proteins; D003300:Copper; D008668:Metallothionein