Development of broad-spectrum bacterial biosensors to assess toxicity due to heavy metals

Summary of the technology offered

A group of researchers from the Laboratory of Signal Transduction in Pathogenic Bacteria, has managed to obtain pluripotent biosensors for toxic metals with the ability to recognize and respond to a wide range of metal ions.

Brief description of the technology offered

The pluripotent biosensors for heavy metals are based on proteins having the ability to detect a wide spectrum of toxic metals and in turn alter gene expression in response to these metals. These sensor proteins were obtained by mutations of the sensors of monovalent metals of Salmonella enterica: the gold sensor GOLS (which preferably detects Au +) and the copper sensor CueR (which detects Cu +, Ag + or Au + with similar affinity). Unlike the original sensors, the mutants obtained are able to recognize and respond to a wide range of divalent metal ions Hg2 +, Zn2 +, Co2 +, Cd2 + or Pb2 +, without losing the original ability to detect ions Cu +, Ag + or Au +.

Using genetic engineering, it was also possible to couple the detection of these metals with the expression of reporter genes that provide an easily measurable signal (as β-galactosidase and GFP), whereby achieving the bacterial biosensor development. Thus, the amount of metal present in the sample can be estimated by measuring the emitted signal. These biosensors allow assessing of both the presence of toxic metals such as (Hg, Pb, Cu, Ag, Au, Zn, Cd and Co) as well as the total content of these in the samples.

Application domain

  • Industries polluting through its effluents.
  • Water treatment plants.
  • Environmental protection agencies.
  • Companies of environmental control.
  • Environmental impact studies.
  • Health.
  • Mining Industry.

Advantages

  • Bacterial biosensors are useful for the analysis of water samples and industrial effluents.
  • The possibility of detecting such a broad spectrum of metals makes them unique to theirkind, since the related protein sensors, previously described, detect only some of these metals.
  • These devices are particularly useful for evaluating toxicity due to heavy metals, since they allow for determining the presence of these metals in the samples by either qualitative or quantitative tests, and they detect only the proportion of these species that are available to living organisms (bioavailable fraction).
  • Fast, economical, simple and sensitive evaluation compared to other methods used for the same purpose.
  • The use of bacterial biosensors andmodified bacteria coupled with a measurable signal for detection of an analyte, is a booming methodology since these devices allow for the development of portable instruments for evaluating field samples.
  • It is possible to use in laboratories with minimal equipment.
  • The development of this equipment being based on biosensors will not require specialized personal for their use, in contrast to other conventional methods (spectroscopic, electrochemical and chromatographic methods), or high costs of maintenance and operation of the instrument.

State of development

  • The prototype (the detection/measurement system inserted in the nonpathogenic bacteria Escherichia coli).
  • It was tested in laboratory conditions.
  • Available for demonstration.
  • Knowledge is ready for development and scaling.

State Intellectual Property

The technology is in the process of protection through the application 20130100783 of 1103/2013 at the National Institute of Intellectual Property-National Management of Patents (INPI). The patent is owned by the National University of Rosario and CONICET.

Its title is “Mutated polypeptide, bacterial strain comprising it and methods to detect different metal cations simultaneously”.

Details of potential operating or partnership agreements

  • Patent licensing.
  • Technology transfer to companies interested in developing measuring devices.
  • Joint Venture.
  • Technical support.
  • Technical cooperation.

Researcher

Dr. Fernando Soncini.