There are diseases/infections that can be caused with a very few number of bacterial cells. Shigellosis is one example.
Microbio facts
Ryder Jones
Luis Cooper
The CFU is a gross underestimation of microbial population, because of the assumption that a single colony arises from a single cell.
Nathan Wilson
This was really cool
en.wikipedia.org
The molecular mechanisms of pathogens like Cholera and Mycobacterium tuberculosis is extremely interesting.
And then, there's Strain 121
en.wikipedia.org
Alexander Lopez
The flagella of archaea,bacteria, and eukarya is a great proof of intelligent design.
Leo Turner
Oh, also, the fact that (but this is more related to life in general, but a bit more to micro-organisms since they can be found in virtually any habitat) the proteins used are comopletely adapted for the environment so they can actually survive. I found that pretty interesting, albeit extremely logical.
Also, chlorosomes and phycobilisomes
en.wikipedia.org
en.wikipedia.org
Jackson Powell
some of the fermenting microbes in your digestive tract produce butyrate which enters your bloodstream. Butyrate regulates ~3% of all you genes (which is a lot) through histone deacetylaze inhibition. This means that small dots inside your digestive tract affect your day to day life by farting.
Brandon Wilson
pretty cool, actually
David James
But for many applications CFUs are what actually matters. Whether it takes one, two or 20, the ability to colonize is what is important.
Connor Roberts
There's this. Oxalate is a major metabolite which contributes to the formation of kidney stones. There's bacteria in our gut that metabolize that shit.
ncbi.nlm.nih.gov
Kayden Bennett
Wolbachia a bacterium that resides inside insect cells. Scientists are currently investigating its effects on preventing the dengue virus from spreading to the Andes mosquitoes.