Production of FK520 by Streptomyces tubercidicus.

The discovery of immunosuppressant compounds created the conditions for the successful transplantations. Effective immunosuppressant compounds were isolated from cultures of different microorganisms, among others macrolide type immunosuppressants, FK506 and FK520, were isolated from the fermentation broths of Streptomyces species. In this study a screening program was carried out to isolate microorganisms, which produce macrolide type immunosuppressant compounds.