Bacteria encyclopedia

Phylum

Actinomycetota

Actinomycetota, formerly Actinobacteria: the phylum of Bifidobacterium and of tuberculosis. Where it lives in your body, what it does for and against you.

Bacillota

Bacillota (once Firmicutes) feeds your gut butyrate and houses C. difficile. What the studies show, and why the 'fat ratio' on a stool test can't diagnose you.

Bacteroidota

Bacteroidota, formerly Bacteroidetes: what this huge gut bacterial group digests for you, when it turns dangerous, and what the named studies found.

Fusobacteriota

Fusobacteriota (formerly Fusobacteria) is a normal phylum — a whole branch — of mouth bacteria. One small clade is linked to colon cancer; most of it is not.

Pseudomonadota

Pseudomonadota, formerly Proteobacteria: what this bacterial phylum does for us, what it does against us, and why a healthy gut keeps its share low.

Verrucomicrobiota

Verrucomicrobiota, formerly Verrucomicrobia, is the gut phylum of Akkermansia muciniphila. What the mucus eater does for you, and against you.

Genus

Bifidobacterium

Bifidobacterium rules the gut of a breastfed baby. What it does for us, what it does against us, and exactly where the evidence stops.

Lactobacillus

What Lactobacillus is, where it actually lives in the body, what the trials show it can and cannot do, and why the genus was split into 25 genera in 2020.

Species

Akkermansia muciniphila

A gut bacterium that feeds on your own mucus lining — and may protect your metabolism. What the named studies show, and where they stop.

Heyndrickxia coagulans

Bacillus coagulans (also Heyndrickxia coagulans — one bug, two names): what this spore-forming probiotic does for mouth and gut, and where the evidence stops.

Clostridioides difficile

Clostridioides difficile, formerly Clostridium difficile: what it is, where it lives, why it harms — and why silent carriage goes with less diarrhoea.

Escherichia coli

Escherichia coli lives in the gut of more than 90 % of people. What it does for us, what it does against us, and where the honest evidence stops.

Faecalibacterium prausnitzii

Faecalibacterium prausnitzii is over 5 % of your gut bacteria and feeds the colon lining. What the named studies show — and what they do not.

Helicobacter pylori

Half the world hosts it. It causes ulcers and gastric cancer, yet goes with less asthma and less oesophageal (gullet) cancer. Proven harm, unproven benefit.

Porphyromonas gingivalis

What Porphyromonas gingivalis is, where it lives, what it does for us and against us — mechanism first, every number traced to a named study.

Streptococcus mutans

What Streptococcus mutans is, where it lives, how it turns sugar into plaque and acid, what it does for and against you — every number with a named study.

Streptococcus salivarius

What Streptococcus salivarius does on your tongue, what its probiotic trials actually show, and the rare infections it causes — every source named.