186 THE ANTIBIOTICS 



ammonium sulfate followed by precipitation from concentrated aque- 

 ous solutions with acetone or alcohol. A lipoid antibacterial substance 

 is extracted with ether from the ammonium sulfate precipitate. 



Chemical and physical properties: Composed of a bacteriolytic enzyme, 

 actinozyme, and of a lipoid antibacterial substance. Stable between 

 pH 5.0 and 9.0 and destroyed by ultraviolet light under 300 nnx. 

 Composed of particles about 4 nni. 



Biological activity: Lyses dead cells of gram-positive or gram-negative 

 bacteria. Dead gram-positive bacteria are less sensitive. Certain living 

 gram-positive bacteria can also be lysed. 



Toxicity: No data. 



Utilization: Has been used in treatment of Staphylococcus infections. 



Reference: Welsch, M., Phenomenes d'antibiose chez les actinomycetes. 

 Duculot (ed) 1947; Gratia, A., Bull. Mem. Acad. Chir., 56, 1930, 

 344-348; Gratia, A., and Alexander, J., Compt. Rend. Soc. Biol., 

 91, 1924, 1442-1443. 



Actinomycin 



Produced by: Streptomyces antibioticus, S. parvus, and other species of 

 Streptomyces. 



Synonyms: Actinomycin A (Waksman and Woodruff); Actinomycin B 

 (Lehr and Berger); Actinomycin X (X x , X 2 ) (Linge). 



Method of extraction: Extracted from the medium with organic solvents 

 (ether, ethyl acetate, or butanol). Crystallizes from ethyl acetate or 

 acetone-ether mixtures as red platelets. 



Chemical and physical properties: Weakly basic, red pigmented substance. 

 Soluble in chloroform, acetone, ethanol, and ethyl acetate. Slightly 

 soluble in water. Stable in aqueous alcohol on boiling. Unstable at 

 acid and alkaline pH. Maximum absorption of light at 230-250 un* 

 and 450 m/j in ethanol. m.p. 250°C. Composed of a quinonic chromo- 

 phore and a peptide formed of five amino acids: threonine, proline, 

 valine, N-methyl valine, and sarcosine. Actinomycin X can be frac- 

 tionated into at least two closely related compounds, Xi and X 2 , 

 which differ in the ratio of the five amino acids that they contain. 

 C61H88N12O16. 



Biological activity: Highly active against gram-positive bacteria and cer- 

 tain fungi. 



Toxicity: Highly toxic, 100 mcg/24 gm mouse causing death in 24 to 48 

 hours. 



Reference: Waksman, S. A., and Woodruff, H. B., Proc. Soc. Exptl. Biol. 

 Med., 45, 1940, 609-614; J. Bacterol., 42, 1941, 231-249; Waksman, 

 S. A., and Tishler, M., J. Biol. Chem. U2, 1942, 519-528; Lehr, H., 



