Streptomyces hygroscopicus

Streptomyces hygroscopicus is a bacterial species in the genus Streptomyces. It was first described by Hans Laurits Jensen in 1931.

Biochemistry
Cultures of different strains of S. hygroscopicus can be used to produce several chemical compounds or enzymes.

Immunosuppressants
Sirolimus (also known as rapamycin) is an antifungal and immunosuppressant that has been isolated from S. hygroscopicus from soil samples from Easter Island. Ascomycin is another immunosuppressant produced by some strains of S. hygroscopicus; it has a similar structure to sirolimus and can be used to treat autoimmune diseases and skin diseases and can help prevent rejection after an organ transplant.

Antibiotics
The antibiotics geldanamycin, hygromycin B, nigericin, validamycin, and cyclothiazomycin are found in S. hygroscopicus.

Experimental cancer drugs
Indolocarbazoles can be found in S. hygroscopicus.

Anthelmintics and insecticides
Milbemycin and milbemycin oxime can be found in S. hygroscopicus cultures.

Herbicide
S. hygroscopicus also produces the natural herbicide bialaphos.

Enzymes
The enzymes alpha,alpha-trehalose-phosphate synthase (GDP-forming), carboxyvinyl-carboxyphosphonate phosphorylmutase, and hygromycin-B kinase can be isolated from cultures of S. hygroscopicus.