Chapter 4 



Characterization of Streptomyces Species 



Important Characters to be Considered 

 for Recognition of Species and Va- 

 rieties of Streptomyces 



In the identification and characterization 

 of Sin pt'innin s species, the following char- 

 acters should be considered: 



1. Morphological properties: 



(a I Structure of substrate 1 mycelium. 



(b) Nature and formation of aerial my- 

 celium. 



(c) Struct ure and branching of sporo- 

 phores. 



(d) Size and shape of spores. 

 (e I Surface of spores. 



2. Cultural properties on various media: 

 (a i ( rrowth characteristics. 



(b) Development of aerial mycelium. 



(c) Color of aerial and substrate my- 

 celium. 



.'!. Biochemical properties: 



(a) Production of soluble pigments in 

 organic and in inorganic media. 



(b) It ilizat ion of carbon sources. 



(c) Starch hydrolysis. 

 id i Sucrose inversion. 



(e) Cellulose decomposition. 



(f) Proteolytic activities: liquefaction of 

 gelatin, bl 1 serum, and casein; co- 

 agulation and peptonization of milk. 



(g) Utilization of nitrogenous com- 

 pounds. 



(h) Formation of oxidases: tyrosinase 

 and laccase. 



(i) Reductases: nitrate reductase, sul- 

 fate reductase. 



(j) Formation of antibiotics and vita- 

 mins. 



(k) Formation of IFS in peptone-iron 

 agar. 



4. Sensitivity to antibiotics: 



(a) Sensitivity to pure antibiotic prep- 

 arations. 



(b) Phenomena of ••cross-resistance" 

 and "cross-sensitivity" on artificial 

 media. 



5. Sensitivity to phages. 



6. Serological reactions. 



7. Chemical composition. 



8. Ecological properties. 



9. Genetic relationships. 



10. Age of <ailt ure. Information should be 

 submitted concerning the age of the cul- 

 ture when the particular properties were 

 studied and the manner in which the 

 culture has been kept in the laboratory. 



11. Type cultures. The culture should be 

 deposited in a recognized collection and 

 the assigned number reported. Every 

 possible means for preservation of the 

 culture should be used. Preservation of 

 strains by lyophilization, soil culture. 

 mineral oil seals on active slants, or 

 storage in deep freeze i- believed to re- 

 duce physiological changes t<> a mini- 

 mum. With the lyophilization technique 

 within the reach of even the small lab- 

 oratory, there is no excuse for an inves- 

 tigator, particularly one publishing on 

 designated strains, to •'lose" his strains. 



In characterizing Streptomyces species, 

 only certain media should be used and well - 



lit 



