Streptomyces
Streptomyces are medically important, as they produce antifungals, antiparasitic drugs, antivirals, antitumorals, anti-hypertensives, immunosuppressants and antibiotics. Different species of streptomyces are used to produce different antibiotics. Over 500 species of Streptomyces bacteria have been described. For example, widely studied S. griseus was the first to be used in production of an antibiotic streptomycin, while S. avermitilis as a source of avermictin. Another well-studied species, S coelicolor, is widely used in genetic studies. Overall, Streptomyces produce over two-thirds of the clinically useful antibiotics of natural origin, such as tetracycline, neomycin and chloramphenicol.