Metabolic Discrimination of Unknown Bacterial Pathogens

A collaboration between Vanderbilt University and the U.S. Army Edgewood Chemical and Biological Center (ECBC) at the Aberdeen Proving Grounds will develop a wide-spectrum, activity-detection technology that employs multiphasic sensing, in order to provide a biofunctional signature of a CBW agent, unknown drug, or other threat. The signatures will be used with advanced algorithms to discriminate between different agents acting on a set of target cell lines. <P> The proposed approach is extraordinarily versatile and general, because we are measuring the biological impact of the toxins, rather than simply their presence. This will address a critically important and as-yet-unmet need for diagnostic tools capable of identifying the mechanism of action of unknown or reengineered threat agents that defy accurate detection by existing, agent-specific sensors. <P> The diagnostic tools will be created to establish signatures of key changes in metabolic and signaling pathways that occur in cell lines responsive to Anthrax, Ricin, Staphylococcal Enterotoxin B (SEB), and Clostridium Botulinum toxins. The interaction of the toxins with cells leads to a multitude of metabolic and signaling events, as toxins disrupt normal cellular functions in specific and non-specific ways that are not yet fully understood.<P> To provide a means to characterize the effects of unknown toxins, the proposed diagnostic system will monitor key parameters of specific metabolic and signaling pathways over a spectrum of time- and volume-scales. Newly developed well-plate protocols for end-point metabolic rates will be coupled with commercial fluorescence assays for signaling events. <P> Additionally, the same metabolic and signaling events will be captured as dynamic biosignatures using a modified Cytosensor that simultaneously monitors multiple analytes on the time scale of minutes.<P> This approach will be scaled down to achieve dynamic resolution on the order of seconds in a microfabricated NanoPhysiometer. This approach should find wide application in the discovery of new drugs and unexpected and/or undesired physiological activity; environmental and industrial toxicology; metabonomics and signaling; and screening of countermeasures, therapies, and prophalaxis for pathogenic bacteria and toxins.