Which bacterium produces streptomycin, the antibiotic discovered in the 1940s?

Streptomyces griseus produces streptomycin, the antibiotic discovered in the 1940s.

Selman Waksman and his student Albert Schatz isolated streptomycin from S. griseus in 1943. It became the first effective antibiotic treatment for tuberculosis and helped establish soil-dwelling actinomycetes as an important source of medicines.

Streptomyces species are filament-forming bacteria that live mainly in soil. Their branching growth can resemble fungal hyphae, which is why they were historically mistaken for fungi. They also produce the earthy-smelling compound geosmin.

Streptomycin is not produced by Streptococcus, despite the similar name. Nor is S. griseus the bacterium responsible for tuberculosis; that disease is caused mainly by Mycobacterium tuberculosis.