Amperometric measurement of copper ions with a deputy substrate using a novel Saccharomyces cerevisiae sensor.
The first microbial biosensor to detect Cu2+ by an amperometric method has been developed. For this purpose, recombinant Saccharomyces cerevisiae strains are suitable as the microbial component. These strains contain plasmids with the Cu2+-inducible promoter of the CUP1-gene from Saccharomyces cerevisiae fused to the lacZ-gene from E. coli. On this sensor the CUP1 promoter is first induced by the Cu2+-containing probe and subsequently lactose is used as a deputy substrate to make the measurement. If Cu2+ is present in the sample, these recombinant strains are able to utilize lactose as a carbon source, which leads to alterations in the oxygen consumption of the cells. The sensor measured Cu2+ in a concentration range between 0.5 and 2 mM CuSO4. In addition, an indirect amperometric measurement principle was developed which allows the detection of samples containing Cu2+ and fast biodegradable substances.
Lehmann
M
M
Institut fuer Pflanzengenetik und Kulturpflanzenforschung, Gatersleben, Germany.
Riedel
K
K
Adler
K
K
Kunze
G
G
D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods*; D002352:Carrier Proteins; D018914:Cells, Immobilized; D003300:Copper / Q000032:analysis*; D004926:Escherichia coli / Q000235:genetics; D005800:Genes, Fungal; D007763:Lac Operon; D007785:Lactose / Q000378:metabolism; D008668:Metallothionein / Q000235:genetics / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D010957:Plasmids / Q000235:genetics; D011401:Promoter Regions, Genetic; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D013379:Substrate Specificity
C500769:CUP1-1 protein, S cerevisiae; D002352:Carrier Proteins; C007121:copper thionein; D003300:Copper; D008668:Metallothionein; D007785:Lactose