Lambdamycin-producing strains were detected by means of the BIP test method. The isolation technique and the physicochemical and biological properties of lambdamycin, a n antibiotic produced by Streptomyces glaucoaehromogenea, are described. Lambdamycin is a yellow-green pigment of the chromoglycoside type. Digitalose and fucose are the sugar components. The physicochemical properties of lambdamycin resemble those of chartreusin. However, the known biological activity is different. The antibiotic can be isolated from culture filtrates and from the mycelium by extraction with lower aliphatic alcohols. It can be purified by gel filtration methods. Lambdamycin displays antimicrobial activity, particularly against grampositive bacteria. Strains which produce enzymes inactivating different commercial antibiotics are also inhibited. Moreover, lambdamycin shows antiviral activity, as well as cancerostatic and ergotropic action in vitro and i n vivo. The acute LD,, of lambdamycin in mice after 21 days was >125 mg/kg when administered intraperitoneally.
Fiir eine gezielte Suche nach neuen Antibiotics mit potentiell cancerostatischerAktivitat gegen tierexperiinentelle Tumoren setzten wir eine Reihe von molekularbiologischen Screening-Modellen ein, die eine rationelle Vorauswahl von Inhibitoren des Nucleinsaure-Stoffwechsels und dessen Regulation gestatten (FLECK 1970).Uber Ergebnisse und Erfahrungen nach mehrjahriger Anwendung des molekularbiologischen Screening-Programms ist bereits berichtet worden (FLECK 1974