Outside the host, endospores remain metabolically-dormant, preserving virulence even when exposed to harsh environmental conditions. Endospores are the anthrax contagion, entering the body where they are phagocytosed by regional macrophages. After escape, massive bacteremia, toxemia and death ensue. We are examining each of these stages and defining discrete mutants blocked at each step. Our data indicate that anthrax endospores have unique in vivo sensory and signalling mechanisms for triggering germination.
Germination occurs rapidly in cultured macrophages.
Non-pathogenic Bacillus sp. We employ, as experimental tools, methods of molecular pathogenesis, functional genomics and functional proteomics. Understanding this rapid and dramatic switch, from absolute metabolic dormancy of the endospore to growing virulent bacilli allows anthrax to be exploited as an effectual model for examining the earliest stages of a bacterial infectious cycle. T. Dixon, A. Fadl, T. Koehler, J. Swanson and P. Hanna. 2000. T. Dixon, B. Meselson, J. Guillemin and P. Hanna. 1999.