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<i>Bacillus cereus</i> is a spore-forming ubiquitous bacterium notable as a food poisoning agent. Detection of <i>B. cereus</i> spores using selective media is laborious and non-specific. Herein, the quantitative detection of <i>B. cereus</i> spores was investigated with commercial antibodies and published aptamer sequences. Several detection reagents were screened for affinity to <i>Bacillus</i> collagen-like protein A (BclA), an abundant exosporium glycoprotein. Sensitivity and selectivity toward <i>B. cereus</i> spores were tested using immunoassays and multi-analyte profiling (xMAP). A recombinant antibody developed in llama against BclA protein showed <i>B. cereus</i> spore selectivity and sensitivity between 10² and 10⁵ spores/mL using xMAP. DNA aptamer sequences demonstrated sensitivity from 10³ to 10⁷ spores/mL and no cross-reaction to <i>B. megaterium</i> and <i>B. subtilis</i>. Selectivity for <i>B. cereus</i> spores was also demonstrated in a mixture of several diverse microorganisms and within a food sample with no compromise of sensitivity. As proof of concept for multiplexed measurement of human pathogens, <i>B. cereus</i> and three other microorganisms, <i>E. coli, P. aeruginosa</i>, and <i>S. cerevisiae</i>, were simultaneously detected using xMAP. These data support the development of a rapid, sensitive, and selective system for quantitation of <i>B. cereus</i> spores and multiplexed monitoring of human pathogens in complex matrices.