fission

budding

Bacteria grow and reproduce on solid media. Within a few days, one or several bacteria can divide and multiply to produce thousands of cells, which gather together to form a visible group called a colony.

A colony is formed by the growth and reproduction of one bacterial cell

Grows in the medium or on the surface of the medium, and its main function is to absorb nutrients

Mycelium grows from the hyphae in the base and extends into the space outside the culture base.

When the aerial hyphae grow and develop to a certain stage, the aerial hyphae differentiate into spore-forming hyphae.

When the spore filaments grow to a certain stage, they break into spores, or conidia.

Actinomycetes divide spore filaments into a cluster of conidia by producing a diaphragm.

Actinomycetes can also use fragments of broken mycelium to form new mycelium. This phenomenon is common in liquid culture. This is how actinomycetes multiply during industrial fermentation to produce antibiotics. If cultured statically, a bacterial film often forms on the surface of the culture, and spores can also grow on the film.

Some actinomycetes are coiled with hyphae to form sporangia, with transverse septa between them to produce spores. When the cysts mature, the spores are released. Cysts can be formed on aerial hyphae or on basal hyphae.

When the vegetative hyphae of Nocardia become mature, they will suddenly produce bacillary, spherical or branched conidia with uniform shapes and sizes by dividing horizontally.

① There is no complex peptidoglycan network structure, but a surface layer of protein or glycoprotein

②Does not contain muramic acid, D-amino acids and diaminopimelic acid, and is composed of pseudo-peptidoglycan (N-acetylglucosamine and N-acetyltaluronic acid as the backbone) with β-1,3-glycosidic bonds constitute

③Not affected by lysozyme hydrolysis and penicillin action