[5][7] Found predominantly in soil and decaying vegetation, most streptomycetes produce spores, and are noted for their distinct "earthy" odor that results from production of a volatile metabolite, geosmin.

[5] Streptomycetes produce over two-thirds of the clinically useful antibiotics of natural origin (e.g., neomycin, streptomycin, cypemycin, grisemycin, bottromycins and chloramphenicol).

When Selman Waksman and Arthur Henrici in 1943 divided Actinomyces genus into narrower genera, they failed to find a valid generic name for aerobic sporulating species so had to coin a new one.

The genus Streptomyces includes aerobic, Gram-positive, multicellular, filamentous bacteria that produce well-developed vegetative hyphae (between 0.5-2.0 μm in diameter) with branches.

[17] In some species, aerial hyphae consist of long, straight filaments, which bear 50 or more spores at more or less regular intervals, arranged in whorls (verticils).

Each branch of a verticil produces, at its apex, an umbel, which carries from two to several chains of spherical to ellipsoidal, smooth or rugose spores.

[22] The genome sequence of S. scabiei, a member of the genus with the ability to cause potato scab disease, has been determined at the Wellcome Trust Sanger Institute.

At 10.1 Mbp long and encoding 9,107 provisional genes, it is the largest known Streptomyces genome sequenced, probably due to the large pathogenicity island.

[5] Intriguingly, a correlation has been observed between the number of carbohydrate-active enzymes and secondary metabolite biosynthetic gene clusters (siderophores, e-Polylysin and type III lanthipeptides) that are related to competition among bacteria, in Streptomyces species.

The properties of the secretion system is an advantage for industrial production of heterologously expressed protein because it simplifies subsequent purification steps and may increase yield.

[37] Almost all of the bioactive compounds produced by Streptomyces are initiated during the time coinciding with the aerial hyphal formation from the substrate mycelium.

[16] Streptomycetes produce numerous antifungal compounds of medicinal importance, including nystatin (from S. noursei), amphotericin B (from S. nodosus),[38] and natamycin (from S. natalensis).

Members of the genus Streptomyces are the source for numerous antibacterial pharmaceutical agents; among the most important of these are: Clavulanic acid (from S. clavuligerus) is a drug used in combination with some antibiotics (like amoxicillin) to block and/or weaken some bacterial-resistance mechanisms by irreversible beta-lactamase inhibition.

S. avermitilis is responsible for the production of one of the most widely employed drugs against nematode and arthropod infestations, avermectin,[56] and thus its derivatives including ivermectin.