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Bacillus anthracis and Yersinia pestis are biological agents that pose an increasing concern to national security if deliberately disseminated. Hoax agents, including suspicious white powders and environmental bacterial species, can also cause disruption. In either scenario it is of high importance to rapidly and accurately identify any suspicious powder as hazardous or hoax. Protein profiling, using microfluidic capillary electrophoresis, provides a rapid (less than 40 minutes), reliable and field-based screening method. Two commonly encountered hoax agents, three Bacillus species (including B. anthracis Sterne strain), two Yersinia species and E. coli were profiled on the Experion™ System (Bio-Rad). Peak detection algorithms were developed for the identification of protein peaks in electropherograms. Boolean logic paths were then employed to predict the electrophoretic pattern of samples. Parameters assessed included variation within and between Experion™ Pro260 chips and the ability to discriminate between samples over time intervals, between operators and between field and laboratory analyses. Classification with optimal Boolean logic paths reported no misclassification with an accuracy of 100% for B. anthracis Sterne strain, B. thuringiensis (powder and culture-based), B. cereus and plain wheat flour. Overall there was 75% correct identification for the eight sample types tested. [ABSTRACT FROM AUTHOR]

Yersinia pestis is a biological agent of high risk to national security due to its ability to be easily disseminated and transmitted among humans. If Y. pestis was to be utilized in a deliberate disease outbreak it would be essential to rapidly and accurately identify the agent. Current identification methods for Yersinia species are limited by their reliance on cultivation, the time taken to achieve results and/or the use of protocols that are not amenable for field use. Faster identification methods are urgently required. Microfluidic capillary electrophoresis was used to identify seven Yersinia species based on their protein profiles. Further objectives included determining if Yersinia species could be detected in mixtures of milk products and Escherichia coli, determining if Yersinia could be detected in a blinded identification and reproducibility across two platforms. Two characteristic protein bands were detected at 50 kilodaltons (kDa) and between 50 and 75 kDa for the Yersinia species. Individual Yersinia species could be differentiated from one another and distinguished from E. coli, Bacillus anthracis Sterne strain and Dipel (containing Bacillus thuringiensis). Due to the high protein content of milk products Yersinia could not be detected when mixed with these but was detected when mixed with E. coli. Species were correctly identified with 96% success in blinded procedures using 12 individuals. Whilst protein profile patterns were reproducible across platforms there was some discrepancy in protein sizing. This study demonstrates that protein profiling using microfluidic capillary electrophoresis is able to rapidly and reproducibly identify and characterize Yersinia species. Results show this technique is a powerful front-line, rapid and broad range screening method capable of identifying and differentiating biological agents, hoax agents and environmental bacterial species. [ABSTRACT FROM AUTHOR]

Purpose: In recent times, but especially since 2001, bioterrorism has been of increasing concern. In addition to the use of biological agents, including Bacillus anthracis (anthrax), there have been numerous hoax white powder 'scares.' It is imperative to rapidly and accurately identify any suspicious powder as hazardous or hoax. Classical methods for identification typically rely on time-consuming cultivation or highly specific molecular tests which are limited if the agent is unknown. Faster and field portable methods for analysis of suspicious powders are urgently required. Methods: Potential hoax agents, including Bacillus species and household powders, were analyzed using automated microfluidic capillary electrophoresis to determine if protein profiling can distinguish between, and identify, samples. Results: Distinctive protein profiles were produced for Bacillus species, with the presence and/or absence of certain bands, aiding identification. In particular B. anthracis Sterne strain contained a distinctive doublet band above 100 kDa which was not present in any other Bacillus species or hoax agents examined. The majority of powders produced distinctive banding that could enable the identification of the sample while simultaneously ruling out B. anthracis with a high degree of confidence. Conclusions: Results show automated microfluidic capillary electrophoresis can rapidly and reproducibly characterize Bacillus species and hoax agents based on protein profiles without the need for culture. Results were reproducible and there was enhanced resolution and rapidity compared to traditional protein profiling methods. Results show this technique is amenable to field use at a bioterrorism incident, thereby providing essential information to investigators regarding containment and treatment strategies. [ABSTRACT FROM AUTHOR]