At the Quadram Institute, we’re interested in microbes, and how they interact with us. We carry trillions of microbes on and in our bodies. This population of microbes is known as the microbiota, or microbiome, and we’re now starting to realise how important it is to our health.

Understanding the microbiome in the human gut is a major focus for Quadram Institute researchers. As well as microbes that benefit us, we’re also studying microbes that cause disease, especially ones that get into our bodies on food. As well as helping ensure our food safety, this will help battle other global problems like the emergence of antimicrobial resistance.

This information sheet on microbes was developed in Autumn 2017 as part of the Quadram Institute’s displays at the Norwich Science Festival.


Bacteroides are some of the most common members of our gut microbiome. They play a crucial role in fermenting plant-based foods, helping to keep us healthy


Bifidobacterium are bacteria that make up a healthy microbiome, and are some of the earliest colonisers of a healthy gut


Campylobacter are the most common cause of food poisoning in the UK. Most cases are linked to poultry meat, so take care handling raw chicken

Clostridium difficile

Clostridium difficile infections are most common after your natural microbiome has been depleted, perhaps by antibiotics


There are many different strains of E.coli, most of which are harmless, and can make up useful members of our microbiota. Some strains, however, cause food poisoning


Listeria cause listeriosis, a severe form of food poisoning. People with weakened immune systems (the elderly, pregnant women, new born babies) are especially vulnerable


Ruminococcus bacteria break down fibre, which has been linked to health benefits. Eating a high fibre diet keeps these members of the microbiome healthy, and therefore us too.


Salmonella can cause serious food poisoning. Proper cooking, storage to prevent cross-contamination, and good hygiene can reduce its spread and cut the risk of infection

Download the ‘Meet the microbes’ information sheet

For more information, please contact

Thank you to the QI researchers who helped put this information together, in particular Mark Kirkwood for the cartoons, as well as Andy Goldson, Stephanie Schüller, Kathryn Cross and Mary Parker and all who helped with images.