Catalytic Antibodies Which Mimic Urease Activity

The department of Defense is currently engaged in extensive biosensor research and development efforts. A major goal of these efforts id the development of automated field-usable systems for the detection of a variety of analytes including toxins, infectious organisms, and chemical agents in either environmental samples or clinical specimens. These materialsmay be naturally accuring or result form the use of chemical and biological weapons. Many biosensors are based on immunoassay techniques and require stable enzyme/substrate reagents capable of transducing a signal to the detector. The goal of this Phase I project is to generate catalytic antibodies which can generate ammonia by the hydrolysis of urea derivative and use these antibody/substrate combinations instead of urease/ures as the indicator reagents in a Threshold asssay for botulinum toxin. Candidate abzymes will be screened directly by Threshold analysis, during preliminary selection. Further catalyst and assay development will also be performed directly in the Threshold. It is expected that a rugged catalyst, of high specific activity for immediate use with the Threshold device will result from this research.