Propionibacterium
Propionibacterium is a gram-positive, anaerobic, rod-shaped genus of bacteria named for their unique metabolism: They are able to synthesize propionic acid by using unusual transcarboxylase enzymes.
| Propionibacterium | |
|---|---|
| Emmental cheese made using Propionibacterium freudenreichii subsp. shermanii | |
| Scientific classification | |
| Domain: | Bacteria |
| Phylum: | Actinomycetota |
| Class: | Actinomycetia |
| Order: | Propionibacteriales |
| Family: | Propionibacteriaceae |
| Genus: | Propionibacterium Orla-Jensen 1909 (Approved Lists 1980) |
| Type species | |
| Propionibacterium freudenreichii van Niel 1928 (Approved Lists 1980) | |
| Species | |
| |
Its members are primarily facultative parasites and commensals of humans and other animals, living in and around the sweat glands, sebaceous glands, and other areas of the skin. They are virtually ubiquitous and do not cause problems for most people, but propionibacteria have been implicated in acne and other skin conditions. One study found the Propionibacterium was the most prevalent human skin-associated genus of microorganisms.
In ruminants, propionibacteria reduce nitrate to nontoxic nitrogen compounds.
Members of the genus Propionibacterium are widely used in the production of vitamin B12, tetrapyrrole compounds, and propionic acid, as well as in the probiotics and cheese industries.
The strain Propionibacterium freudenreichii subsp. shermanii is used in cheesemaking to create CO2 bubbles that become "eyes"—round holes in the cheese.