coryneform

Coryneform refers to a morphological description of bacteria. It describes bacteria that are club-shaped or irregular in form, often appearing as short, slightly curved rods. This shape is distinct from the more common rod-shaped (bacillus) or spherical (coccus) morphologies. The term "coryneform" is derived from the Greek word "koryne," meaning club.

These bacteria are Gram-positive, meaning they retain a crystal violet stain during Gram staining. They are typically non-motile and non-spore-forming. While the term describes a shape, many bacteria fitting this description belong to the phylum Actinobacteria, though not all coryneform bacteria are necessarily Actinobacteria.

A well-known example of a coryneform bacterium is Corynebacterium diphtheriae, the causative agent of diphtheria. However, the term is also applied to a broader group of bacteria that share this characteristic morphology, regardless of their specific taxonomic classification. The shape can be influenced by growth conditions and the age of the bacterial culture. Observing this morphology can be a useful initial step in bacterial identification, often followed by biochemical tests and genetic analysis for precise classification.