Hey, Alarming Anthrax Readers!
How could one come into contact with the very rare Anthrax disease? Well, the main way is through contact with spores. Specifically, the Bacillus anthracis endospores!
http://faculty.ccbcmd.edu/courses/bio141/lecguide/unit1/prostruct/endobant.html
In the image above, the endospores of B. anthracis are depicted with tiny white circles, but here’s a close-up:
http://bio1151.nicerweb.com/Locked/media/ch27/endospore.html
This image shows a zoomed-in view of the endospore, in the very center of the bacterium. There is a coat surrounding the spore that provides additional protection, especially in the soil.
Bacillus anthracis inhabits the soil where animals graze, and if an animal ingests or inhales components of the soil they could be exposed to anthrax. Humans can also get infected when handling these animals or inhaling the spores of the bacterium (which will be further explained in the next post).
Binary fission is a general asexual reproductive process completed in most bacteria, in which the original bacteria replicates its genome and then splits into two, to produce an exact copy of itself. The disease associated with this microbe is interesting– It was believed at one time that having a host was essential for the reproduction of the Bacillus anthracis, but science has proven otherwise. B.anthacis can reproduce in the soil and inside of its host. The endospore is the key component to spreading anthrax, and when it is first formed it is not typically in its active state. The spore is actually created in essential times of distress for the bacteria to stay alive. It becomes active and vegetative when there are nutrients in the soil or inside of the host body like water, sugar, and glucose to help the bacterium thrive. The vegetative form of the spore is what causes anthrax in the host, and it replicates and spreads throughout the body, enhancing the infection. The typical generation time for Bacillus anthracis is 30 to 60 minutes, and the optimal temperature for growth and reproduction is 37 degrees Celsius The temperature cannot exceed 43 °C.
This visual explains the general endospore movement from the soil to the host.
This microbe is a facultative anaerobe, so it does not need oxygen for its survival. However, for the production of endospores essential for infection, oxygen is required.
The Bacillus anthracis is believed to be heterotrophic because other organisms within the bacillus grouping are also heterotrophic. Nutrition is a tricky aspect of this microbe– researchers are not completely sure what this bacterium eats and what is specifically needs to stay alive for sure. Microbiologists have discovered that with each strain of B. anthracis, the nutritional requirements can be slightly different. A commonality found among all strains is that glucose, methionine, thiamine, and amino acids for a source of nitrogen in a complex media are needed at the least to grow this microbe.
It has been said that Bacillus anthracis is an easy bacterium to cultivate in the lab, but this not any information on the internet with detailed steps of how to grow the microbe in a lab– for understandable reasons. Anthrax has been used as a form of bioterrorism in the past through the postal system, so the precise method of how to curate it online (thankfully) does not exist.
https://www.ph.ucla.edu/epi/bioter/anthraxlifecycle.html
This picture depicts the overall life cycle of anthrax and B. anthracis.
Citations:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2784286/
http://ur.umich.edu/0304/Feb16_04/21.shtml
https://www.cdc.gov/anthrax/basics/index.html
https://www.ncbi.nlm.nih.gov/books/NBK7699/
https://www.sciencedirect.com/science/article/pii/S0098299709000557