Abstract
A bacterial sensing system that responds selectively to antimonite and arsenite has been investigated. The bacteria used in these studies have been genetically engineered to produce the enzyme β-galactosidase in response to these ions. This is accomplished by using a plasmid that incorporates the gene for β-galactosidase (reporter gene) under the control of the promoter of the ars operon. This plasmid also encodes for the ArsR protein, a regulatory protein of the ars operon, which, in the absence of antimonite or arsenite, restricts the expression of β-galactosidase. In the presence of antimonite or arsenite the ArsR protein is released from the operator/promoter region of the ars operon and β-galactosidase is expressed. The activity of this enzyme was monitored electrochemically using p-aminophenyl β-D-galactopyranoside as the substrate. The bacterial sensing system responds selectively to arsenite and antimonite (and to a lesser extent arsenate) and shows no significant response to phosphate, sulfate, nitrate, and carbonate.
Original language | English (US) |
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Pages (from-to) | 16-20 |
Number of pages | 5 |
Journal | Analytical Chemistry |
Volume | 69 |
Issue number | 1 |
DOIs | |
State | Published - 1997 |
Externally published | Yes |
ASJC Scopus subject areas
- Analytical Chemistry