Biotechnology Research Series: Video 13

By offering some protection against future illnesses, the microbiome plays a critical role for its host.

Different infections are considered to shape this process, known as colonisation resistance, over the course of the host's lifetime, although the mechanism is not well understood.

Researchers at the National Institutes of Health's (NIH) NIAID Microbiome Program have shown that bacteria in the gut microbiota of people who have previously been infected have increased their resistance to infection.

Furthermore, their findings imply that taurine—an amino acid present naturally in foods like meat, fish, and eggs—could cause the microbiota to become more resistant.

The discovery could boost efforts to find antibiotic alternatives.

Antibiotics disrupt the microbiota and become less efficient when bacteria acquire drug resistance, therefore finding alternatives is an important field of infectious disease research.

Given the relatively recent recognition of the microbiome's participation in a variety of processes, it's critical to understand the role of the microbiota in infections when looking for or improving natural antibiotic alternatives.

When microbiota from previously infected mice was transplanted to germ-free animals, researchers discovered that it helped prevent infection with Klebsiella pneumoniae.

Infection causes host taurine production and the proliferation of taurine utilizers, according to the researchers.

They went on to discover a bacteria class called Deltaproteobacteria that is involved in battling these diseases.

They discovered that taurine is the catalyst for Deltaproteobacteria action.

Taurine is plentiful in the brain, retina, muscle tissue, and organs throughout the body, despite the fact that it is not integrated into proteins.

It's sold as a supplement and even added into sports beverages on the basis of dubious claims that it can improve athletic performance.

Taurine is contained in bile acids in the intestines and aids in the digestion of fats and oils.

Taurine produces the deadly gas hydrogen sulphide as a byproduct.

According to the scientists, taurine increases the microbiota's synthesis of sulphide, an inhibitor of cellular respiration that is a major component of pathogen host invasion.

As a result, pharmacological sulphide sequestration disrupts the microbiota's makeup and encourages disease invasion.

They claim that sulphide sequestration "unleashes endogenous respirers" in the gut microbiota. Low amounts of taurine allow infections to colonise the gut, while high levels produce enough hydrogen sulphide to hinder colonisation, according to the findings.

The researchers discovered that a single, mild infection is enough to prime the microbiota for future infections, and that the liver and gallbladder, which generate and retain taurine-containing bile acids, can build long-term infection resistance.

They discovered that giving mice taurine as a supplement in their drinking water prepared the microbiota to fight illness.

Because bismuth reduces hydrogen sulphide production, infection protection diminished when mice drank water containing bismuth subsalicylate, a common over-the-counter medicine used to treat diarrhoea and upset stomach.

This research "reveals a procedure by which the host, driven by infection, can deploy taurine as a nutrient to nourish and train the microbiota, boosting its resistance to repeated infection," according to the scientists.