ANTIBIOTICS OF ACTINOMYCETES 203 



Utilization: Unknown. 



Reference: Ogata, K., J. Antibiotics (Japan), 3, 1950, 440-444. 



Dihydrostreptomycin 



Produced by: Chemical derivation from streptomycin. 



Production: Hydrogenation of streptomycin in aqueous solution with a 

 platinum catalyst at atmospheric pressure. The aldehyde fraction of 

 the streptose in the streptomycin molecule retains two atoms of 

 hydrogen. 



Chemical and physical properties: Granular white solid, m.p. 215-225°C; 

 [a]f = —88.7° in water. Not inactivated by cysteine and hydroxyl- 

 amine. C21H41N7O12. 



Biological activity: Same as streptomycin. 



Toxicity: Vestibular disturbance less than with streptomycin. Auditory im- 

 pairment more common with dihydrostreptomycin than with strep- 

 tomycin. 



Utilization: Same as streptomycin. 



Reference: Peck, R. L., Hoffhine, C. E., and Folkers, K., J. Am. Chem. Soc, 

 68, 1946, 1390-1391; Heck, W., Hinshaw, H. C, Lyght, C. E., and 

 Hawkins, Z. E., Minutes 12th V. A. Conf. Chemotherapy of Tuber- 

 culosis, Atlanta, 1953, p. 125-133, 294-295. 



Ehrlichin 



Produced by: Streptomyces lavendulae. 



Method of extraction: Culture nitrate adjusted at pH 2.0 with concentrated 



HC1. A dark brown precipitate collected by centrifugation. 

 Chemical and physical properties: Stable at neutrality and alkaline pH. 



Nondialyzable. Inactivated in vitro by horse serum. Unaffected by 



tryptic digestion. 

 Biological activity: Inhibitory to influenza A and influenza B in vitro. Active 



in vivo against influenza B. Inactive against bacteria, fungi, Chlamy- 



dozoaceae, pox viruses, and bacterial viruses. 

 Toxicity: LD (mice), intraperitoneal, 100 mg/kg; subcutaneous, 300 mg/kg. 

 Utilization: None. 

 Reference: Group6, V., Frankel, J. W., Lechevalier, M. P., and Waksman, 



S. A., J. Immunol., 67, 1951, 471-482. 



Endomycin 



Produced by: Streptomyces sp., related to S. albus. 

 Synonym: Closely related to helixin. 



Method of extraction: Antibiotic present largely in mycelium. Extraction 

 with butanol, concentration to a gum, extraction with ether, evapora- 



