Corynebacterium | - gram-positive, non-sporeforming irregular rods
- non motile, slightly curved rods
- some cells stain unevenly
- facultative anaerobes
- mesophiles
- in environment, plants, animals
- spoilage of vegetable and meat products |
Corynebacterium example | - Corynebacterium glutamicum: used for production of glutamic acid |
Brevibacterium | - gram-positive, non-sporeforming irregular rods
- non motile, aerobic
- can change from rod to coccoid shape
- mesophilic
- some species spoil protein-rich foods
- found in raw milk and some cheese
- can be found on human skin |
Brevibacterium examples | - Brevibacterium linens: produces methanediol in some surface ripened cheeses to give aroma - Brevibacterium casei |
Propionibacterium | - gram-positive, non-sporeforming irregular rods
- non motile, pleomorphic rods
- coccoid, bifid, or branched
- single or in short chains
- V and Y configurations and in clumps
- anaerobic
- used in cheese production
- mesophilic |
Propionibacterium example | Propionibacterium freudenreichii, P. shermanii - used in production of swiss cheese - produce proline and propionic acid - found in raw milk, swiss cheese, and silage |
Bifidobacterium | - gram-positive, non-sporeforming irregular rods
- non motile rods of various shapes
- single or in chains, V or star-shaped arrangements
- anaerobic, mesophilic
- produce lactate and acetate from carbohydrates
- used in production of fermented milks
- some species used in probiotics |