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Development of Bioluminescent Sensors to Control Contaminants in the Air, Water, and Soil of Closed Ecosystems.    L. Yang1, V.A. Kratasyuk2.1Dept. of Physics, Carnegie Mellon Univ., Pittsburgh, PA. 2Dept. of Biophysics, Krasnoyarsk State Univ., Krasnoyarsk, Russia

   The environmental control of contaminants in closed ecological life support systems is crucial for the long term success of human space exploration. It will be vitally important to develop biological sensors to monitor environmental conditions inside closed ecosystems. The purpose of this research is to develop highly sensitive and low cost bioluminescent sensors that are that capable of monitoring multiple aspects of the environment in space life support systems.

   Bioluminescent assays were used to detect contaminants in the air, water, and soil taken from environmental growth chambers at the SLSL (Space Life Science Laboratory) at Kennedy Space Center. Two methods were developed to monitor the levels of toxicity in closed ecological systems: (1) in vivo assay using luminous  recombinant E.coli bacteria with LUX-gene from Photobacterium phosphoreum, (2) in vitro assay using the coupled enzyme system: NADH:FMN–oxidoreductase–luciferase. The biological components of the assay were injected into a microplate. Then test samples were injected into the biological solution. A PerkinElmer Victor2 bioluminometer measured the emission of light.

   The conditions to conduct environmental toxicity assays were determined, including the volume of bacteria required and the standard reaction mixture for the coupled enzyme system. The sensitivities of bioluminescent systems to model pollutants: ethanol and buthanol were determined. The biological systems were found to be highly sensitive to liquid ethanol in 1 µl and buthanol in 2 µl. The bioluminescent assays developed for testing liquids were adapted to test for toxicity in the air. A new bioluminescent method for control of the process of purification of bacteria from water was developed with NanoCeram filters. These preliminary investigations of bioluminescent systems show the advantages of this approach for applications in ecological and space life support monitoring.

(Supported by NASA: SLSTP)