Laboratory strains of Bacillus anthracis lose their ability to rapidly grow and sporulate compared to wildlife outbreak strains

Autoři: Michael H. Norris aff001;  Diansy Zincke aff001;  Owen P. Leiser aff003;  Helen Kreuzer aff003;  Ted L. Hadfied aff001;  Jason K. Blackburn aff001
Působiště autorů: Spatial Epidemiology & Ecology Research Laboratory, Department of Geography, University of Florida, Gainesville, Florida, United States of America aff001;  Emerging Pathogens Institute, University of Florida, Gainesville, Florida, United States of America aff002;  Chemical and Biological Signature Science, Pacific Northwest National Laboratory, Richland, Washington, United States of America aff003
Vyšlo v časopise: PLoS ONE 15(1)
Kategorie: Research Article
doi: 10.1371/journal.pone.0228270


Bacillus anthracis is the causative agent of anthrax in animals and humans. The organism lies in a dormant state in the soil until introduced into an animal via, ingestion, cutaneous inoculation or inhalation. Once in the host, spores germinate into rapidly growing vegetative cells elaborating toxins. When animals die of anthrax, vegetative bacteria sporulate upon nutrient limitation in the carcass or soil while in the presence of air. After release into the soil environment, spores form a localized infectious zone (LIZ) at and around the carcass. Laboratory strains of B. anthracis produce fewer proteins associated with growth and sporulation compared to wild strains isolated from recent zoonotic disease events. We verified wild strains grow more rapidly than lab strains demonstrating a greater responsiveness to nutrient availability. Sporulation was significantly more rapid in these wild strains compared to lab strains, indicating wild strains are able to sporulate faster due to nutrient limitation while laboratory strains have a decrease in the speed at which they utilize nutrients and an increase in time to sporulation. These findings have implications for disease control at the LIZ as well as on the infectious cycle of this dangerous zoonotic pathogen.

Klíčová slova:

Anthrax – Bacillus anthracis – Bacterial spores – Decontamination – Deer – Veterinary diseases – Wildlife – Bacterial sporulation


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2020 Číslo 1