INVESTIGADORES
CERMINATI Sebastian
congresos y reuniones científicas
Título:
A SELECTIVE BACTERIAL BIOSENSOR FOR MONITORING GOLD METAL IONS IN THE ENVIRONMET
Autor/es:
CERMINATI, SEBASTIÁN; SONCINI, FERNANDO C.; CHECA, SUSANA K.
Lugar:
Villa Carlos Paz
Reunión:
Congreso; 44th Annual Meeting - Argentine Society for Biochemistry and Molecular Biology Research; 2008
Resumen:
Whole-cell bacterial biosensors are simple and highly accurate devices to detect toxic compounds in the environment. They consist of genetically engineered bacteria that couple a specific sensor protein with a reporter gene that produces a quantitative response. We have previously characterized a Salmonella enterica serovar Typhimurium Au(I)-sensor, GolS, that transcriptionally controls the expression of factors required for gold resistance. Unlike related proteins, GolS is able to discriminate Au from similar monovalent metal ions, such as Cu and Ag. This feature allowed us to design a bacterial biosensor based on the regulon to detect Au ions in complex environments. We constructed a broad-host range reporter plasmid which carries the gfp gene under the control of the GolS-regulated golB promoter. The reporter system was tested in S. Typhimurium or introduced into GolS-expressing Escherichia coli cells. The fluorescence bacterial biosensor was functionally evaluated under laboratory conditions and calibrated regarding metal sensitivity and selectivity. The sensor bacteria detect concentration of gold ions in the range 10-1000 nM, even in samples containing in addition Ag+ and Cu+ ions. This gold-specific biosensor can be used as a technological tool to enhance recovery of this precious metal from ores and lixiviates, contributing to reduce contamination during mining.