Higher classification Actinobacteridae
Scientific name Actinomycetales
|Lower classifications Streptomyces, Mycobacterium, Actinomyces, Frankia, Amycolatopsis|
The Actinomycetales are an order of Actinobacteria. A member of the order is often called an actinomycete. The actinomycetes are very diverse and contain a variety of subdivisions, as well as yet-unclassified isolates, mainly because some genera are very difficult to classify because of a highly niche-dependent phenotype. For example, Nocardia contains several phenotypes first believed to be distinct species before their differences were shown to be entirely dependent on their growth conditions.
Difficulty of classification
Actinomycetales are Gram-positive, but several species have complex cell wall structures that make the Gram staining unsuitable (e.g. Mycobacteriaceae).