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THE ACTINOMYCETES, Vol. I 



onomy of actinomycetes, that based upon 

 the chemical composition of the cell wall 

 deserves particular consideration (see Chap- 

 ter 9). The results tended to emphasize the 

 close relationship of the actinomycetes to the 

 bacteria and not to the Eumycetes or true 

 fungi. Cummins and Harris (1958) found 

 that the cell walls of the actinomycetes were 

 made up of sugars, amino sugars, and a few 

 amino acids (usually three or four), the 

 general pattern of these components being 

 identical with that of the gram-positive 

 bacteria. The mycelial walls of the fungi are 

 composed entirely of carbohydrate. They 

 proposed a system of classification of the 

 actinomycetes based upon the chemical 

 composition of their cell walls (Table 13). 

 They even went as far as to suggest that the 

 order Actinomycetales be abolished alto- 

 gether and the families of actinomycetes 

 be included with the Eubacteriales. 



Recognition of Certain Groups Among 

 the Actinomycetes 



In order to complete the historical back- 

 ground of classification of actinomycetes, 

 one further aspect must be mentioned, and 

 that is the recognition by many of the earlier 

 investigators that certain individual species 

 of actinomycetes may just as well be given a 

 group characteristic. Sanfelice suggested in 

 1904 that the actinomycetes be divided into 

 three groups as follows: 



1. Streptothrix alba. Colonies opaque to white, 

 covered with calcareous powder, and adhering fast 

 to the medium. On potatoes, growth is rapid, 

 white, with a lime-like surface; pigment remains 

 unchanged, or may become gray; occasionally the 

 color may change to black or straw-yellow. San- 

 felice emphasized that "the superficial observer 

 could create out of a dark culture a new species, 

 without recognizing the original nature of S. alba." 



2. Streptothrix flava, frequently obtained from 

 the dust, shows much variation in pigmentation. 

 Growth lichenoid, intensely yellow. On potatoes, 

 growth is also lichenoid, but color less intense. 

 Color may gradually change on continued transfer, 

 becoming either lighter or deeper orange-red. Ap- 

 parently, this group comprised forms that are now 

 largely considered as Nocardia species. 



3. Streptothrix violacea. Opaque, lichenoid 

 growth, brownish in color, occasionally turning 

 black. On potato, growth is of a bluish amethyst 

 color. 



Foulerton, Chalmers and Christopherson, 

 Langeron, and Brumpt also suggested divi- 

 sion of the pathogenic species into several 

 sections or groups. These were designated as 

 Breviores (A. hovis, A. israeli), Minores {A. 

 astcroides), and Majores (.4. albus, A. chro- 

 mogcncs). These sections correspond to the 

 first three genera in the Waksman and Hen- 

 rici classification, namely, Actinomyces, No- 

 cardia, and Streptomyces. 



Further systems of classification of the 

 various genera, notably Streptomyces, into 

 groups, sections, and series, each of which 

 comprises a number of species, will be dis- 

 cussed in detail in ^"ol. II, Chapters 20 and 

 21. 



