GROUPS AM) SPECIES OF GENUS STREPTOMYCES 



I . Pigmenl deep brown. 

 II. Pigmenl taint brown, golden yellow, 

 or blue. 

 B. No soluble pigmenl on organic media. 

 I. Strongly proteolytic. 

 1 1. Weakly proteolytic. 

 The need for the recognition of species- 

 groups was also emphasized: "All the cul- 

 tures should he divided into groups, the 

 representatives of which have common 

 morphological, physiological and cultural 

 characters. These species-groups may show 

 slighl variations within the groups, when 

 several representatives are compared, but 

 all of them possess in common the main 

 distinguishing characters of the species, and 

 are distinctly different from any othei 

 species-group." 



3. JENSEN'S SYSTEM ( 1930) 



Jensen modified the above system of 

 Waksman, in describing '.to s1 rains of actino- 

 mycetes, largely streptomycetes, isolated by 

 him. These strains were divided into several 

 species-groups. 



A. No pigment produced on protein media. 



1. Red or blue pigments in synthetic media; 

 marked reduction of nitrates. 



Actinomya s violaa us ruber 

 _'. No red or blue pigments. 



a. Typical golden pigmenl in all synthetic 

 media. 



Actinomyces fulvissimus 

 I). Pigmenl not typical; abundanl aerial 



mycelium. 



a 1 . Aerial mycelium on synthetic media 

 dark slate gray; lemon or sulfur- 

 yellow pigments sometimes formed. 

 a 2 . Vegel at ive mycelium on synl he1 ic 

 agar light colored. 



Actinomya s c< llulosat 

 I)-. Vegel ative mycelium on synl hetic 

 agar turning dark. 



Actinomyces olivaceus 

 li 1 . Aerial mycelium greenish- or yellow 

 ish gray; very rapid liquefaction of 

 gelatin and blood serum, 

 a-. Aerial mycelium greenish. 

 . 1 ct\ imin ill i 8 grist iis 



!)'-. Aerial mycelium yellowish. 



. 1 1 1 1 iimn iji i s gi i,<, oflavus 

 B. Typical brown pigmenl in protein media 

 "chromogenus" species I. 



1 . Deep brown growth and pigment in all syn 



thetic media. 



Actinomyces i>lm< ochromo 



IJI n us 



2. Pigment in synl hetic media of ol her color or 



a. Aerial mycelium absent or in traces; 



typical red vegetative mycelium. 

 Actinomyces bobili 

 li. Aerial mycelium more or less abundant . 



a 1 . Typical red pigment in synthetic 



agar. 



.1 ctinomyces erythrochromo- 



l/l II us 



h 1 . Pigment not red. 



a'-'. Aerial mycelium rose to cinna- 

 mon brown. 



Actinomyces r<>s< us 

 !>-. Aerial mycelium abundant, char- 

 acteristic lead gray; light brown 

 pigment in synthetic media. 



Actinomyces diastatochromo- 

 genus 



In a subsequent contribution, Jensen 

 (1931) emphasized again that the term 

 "species" as applied to actinomycetes 

 should Ik 1 used in the sense of Waksman's 

 "species-groups," ora "broad group of strains 

 agreeing in ceitain outstanding morpho- 

 logical and biological features"; otherwise, 

 "every strain of actinomycetes isolated from 

 a plating from an ordinary soil could then 

 he raised to the rank of species." 



4. KRASSILNIKOV SYSTEM ( 19 1 1 I 



'litis system was based primarily upon 

 the morphology of sporophores of the cul- 

 tures and the shape of their spores, and 

 secondarily upon the pigmentation of the 

 culture-. 



A. Sporophores branching monopodially. 



I. Spiral shaped sporophores, produced on 

 hyphae of aerial mycelium. 

 1 . Spores spherical or oval , 



a. Cultures colorless, no1 producing any 



pigment at ion. 



