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Escherichia coli -

This is probably the most commonly known bacterium on this list, and can be found in the human gut. Some strains of E. coli can cause food poisoning, but the majority are harmless or even beneficial, with the ability to aid in digestion and produce vitamin K.

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Lactobacillus acidophilus -

This bacterium can not only be found in the intestines of humans, but also in yogurt and probiotic supplements. It produces lactic acid, which helps create an acidic environment in the gut that inhibits the growth of harmful bacteria and prevents diarrhea.

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Bifidobacterium -

This is another beneficial gut bacterium that aids in digestion and boosts the immune system. It is particularly abundant in the gut of breastfed infants and is thought to play a crucial role in establishing a healthy gut early in life.

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Streptococcus thermophilus -

Yogurts and other dairy products need this bacterium in order to ferment. In fact, the bacterium produces lactase, an enzyme that helps digest lactose, which makes yogurt and other fermented dairy products more easily digestible for people with lactose intolerance.

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Bacillus subtilis -

This bacterium produces antibiotics and enzymes that are often used in probiotics. It is known for its ability to survive in harsh conditions–like heat and radiation–and for its use in agriculture as a way to improve soil health.

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Acetobacter -

If you have ever wondered how vinegar gets its signature acidic taste, it is all thanks to this bacterium. Acetobacter helps ferment vinegar by converting ethanol into acetic acid. Interestingly, it's also used in the production of kombucha, a fermented tea beverage.

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Propionibacterium -

This bacterium contributes powerfully to the flavor and texture found in Swiss cheese. Indeed, this bacterium is the reason why Swiss cheese has its well-known holes, which are formed when Propionibacteria produce carbon dioxide bubbles during fermentation.

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Pseudomonas putida -

This bacterium has truly helped humans in the fight against pollution, as it is able to degrade environmental pollutants, including pesticides and heavy metals. It's also being studied for its potential applications in cleaning up contaminated soil and water.

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Rhizobium -

A symbiotic relationship can usually be found between this bacterium and leguminous plants such as beans, peas, and lentils. The bacterium provides an essential source of nitrogen for the plants, allowing them to grow and thrive in nitrogen-poor soils.

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Mycobacterium vaccae -

Here is another bacterium that can be found in soil. Human exposure to M. vaccae has been shown to stimulate the production of serotonin and reduce inflammation, leading to improvements in mood and stress resilience. It's being investigated for its potential as a natural antidepressant.

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Bacillus thuringiensis -

Organic farming has been significantly helped by this bacterium, as it is used as a biological pesticide. It produces proteins that are toxic to certain insects when ingested, and so it has helped control pests while minimizing negative impacts on the environment.

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Streptomyces -

Bacterial species from the Streptomyces family are prolific producers of antibiotics. They’ve been largely used in medicine, agriculture, and industry to help humans in thousands of ways. For example, it is used to treat tuberculosis and other bacterial infections.

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Saccharomyces cerevisiae -

This bacterium is used in almost every household around the world for baking and brewing, helping to leaven bread and ferment beer. It also has some fundamental uses in biotechnology to produce medicine and biofuels.

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Lactococcus lactis -

Here is another bacterium that helps in the fermentation of cheese and other dairy products. It has also been genetically modified to produce therapeutic proteins and vaccines.

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Clostridium butyricum -

This is yet another bacterium that lives in your gut! It produces butyric acid, which has valuable anti-inflammatory effects and alleviates gastrointestinal disorders like diarrhea and irritable bowel syndrome (IBS).

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Enterococcus faecalis -

Also part of the gut microbiota, E. faecalis helps maintain intestinal health. Interestingly, the more extreme version of this bacterium can cause urinary tract infections and endocarditis. But in its positive form, E. faecalis can be used as a probiotic.

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Bacteroides fragilis - This bacterium is very important in the maintenance of your immune system and intestines. It's being studied for its potential therapeutic uses in autoimmune diseases like multiple sclerosis and inflammatory bowel disease.

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Staphylococcus epidermidis -

This is one of the most important bacterium on this list, and is found on your skin. It helps prevent harmful bacteria from colonizing your skin by creating a biofilm on it. For people who are immunocompromised, this bacterium could cause infections.

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Bacillus coagulans -

Another bacterium that helps maintain gut health, B. coagulans is used as a probiotic to alleviate gastrointestinal symptoms like bloating, gas, and diarrhea. Its ability to survive in harsh conditions have made it suitable for use in food products and dietary supplements.

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Aeromonas hydrophila -

A. hydrophila is a bacterium that helps break down organic matter in aquatic environments. Although it has major advantages for marine biology that humans rely on for food and oxygen, it can cause infections in wounds that result in septicemia.

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Deinococcus radiodurans -

This bacterium has an incredibly extreme resistance to radiation, which has made it perfect for applications in medicine. It's also being studied for its potential to clean up radioactive waste sites, protect astronauts from space radiation, and develop radiation-resistant materials.

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Azospirillum brasilense -

Plants and agricultural spaces are at a significant advantage thanks to this bacterium, which is used a biofertilizer to help plant growth, increase crop productivity, and reduce the reliance on chemical fertilizers.

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Nitrosomonas -

In the natural nitrogen cycle of plants, this bacterium converts ammonia into much-needed nitrites–which play a crucial role in the fertility of soil and nutrient cycling.

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Leuconostoc mesenteroides -

The German cuisine sauerkraut–which is fermented cabbage–relies primarily on this bacterium for the fermentation process. Indeed, a lot of fermented vegetables and dairy products like kefir are indebted to this particular bacterium.

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Akkermansia muciniphila -

The overall metabolic health of humans is kept in check by this bacterium, which includes the heart and intestines of every person on the planet. It is being studied for its potential in treating obesity, type 2 diabetes, and cardiovascular disease.

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Pediococcus -

Pediococcus produces acids that contribute to the preservation and flavor of fermented foods. They're used as starter cultures in the production of sausages, pickles, and other fermented vegetables.

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Methanobrevibacter smithii - Your digestive system would not be the same without this bacterium! It helps produce methane in the gut, which breaks down carbohydrates, and is also responsible for various gastrointestinal disorders, including constipation and IBS.

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Bacillus licheniformis -

Most detergents found in households include an enzyme that is produced by this bacterium. In fact, it has a wide range of enzymes that have been employed in the production of laundry detergents, leather, and biofuels.

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Geobacillus stearothermophilus -

This bacterium has the ability to thrive in high-temperature environments, which has made it incredibly beneficial for food processing and the production of biofuel.

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Bacteroides thetaiotaomicron -

This is another bacterium that is responsible for breaking down complex carbohydrates in the gut. It helps in digestion and nutrient absorption, which nourishes all the cells in the human body and influences metabolism.

Sources: (Biology Wise) (NIH) (Medical News Today) (National Geographic Society) (Healthline) (Britannica)

See also: Do you really know how antibiotics work?

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