38 



THE ACTINOMYCETES, Vol. I 



mycetes was observed, including S. albus, S. 

 bobiliae, S. ruhescens, and A^. cuniculi. Grein 

 and Myers also demonstrated the occurrence 

 of various actinomycetes in marine sedi- 

 ments. They suggested that this is due to 

 their salt tolerance and to their ability to 

 survive for considerable periods of time un- 

 der marine conditions. 



Various observations have been made con- 

 cerning the ability of certain types of actino- 

 mycetes to become adapted to high salt en- 

 vironments. This adaptabilit}^ is particularly 

 marked in organisms found in salt lake 

 muds. Nadson observed, in 1903, the pres- 

 ence of actinomycetes in curative salt muds ; 

 he believed that they were concerned with 

 the decomposition of proteins, liberation of 

 ammonia and hydrogen sulfide, and result- 

 ing in the precipitation of CaC03 . Sawjalow 

 claimed to have found an actinomycete, 

 designated as A. pelogenes, in black mud, 

 frefjuently used for curative purposes, in the 

 region of Odessa ; the black color of the mud 

 was said to be due to the biological reduction 

 of the sulfate by the actinomycete. It is now 

 believed, however, that this was a bacterial 

 culture. Lssatchenko (1927) suggested that 

 the low salt concentration of the lakes stud- 

 ied by Nadson may have played an impor- 

 tant function in favoring the activities of 

 the actinomycetes. lssatchenko himself 

 found these organisms also in lakes with 

 high salt concentrations. However, they 

 grew in culture only with a much lower con- 

 centration of salt, namely 10 per cent NaCl. 

 Tender these conditions, proteins were ac- 

 ti\-ely decomposed with the formation of 

 ammonia and H2S. lssatchenko explained 

 the fr('(|uent occurrence of actinomycetes in 

 lake muds with high salt concentration as 

 due to the survival of contaminants from 

 surrounding fields. Further studies on the 

 occurrence of actinomycetes in salt lakes 

 were nuidc by lssatchenko (19;)8) and 

 Kubeutchick (1948). 



Occurrence of Actinomycetes in Lake 

 and River Waters 



Fresh water lakes contain an abundance 

 of actinomycetes. Kedzior first established 

 in 1896 that thermophilic actinomycetes are 

 found in river water. They were also found 

 in sewage. They grew well at 60°C. 



Price-Jones described in 1900 three cul- 

 tures of actinomycetes that would now be 

 classified in the genus Streptomyces, which he 

 isolated from lake and river water. 



The numbers of actinomycetes in fresh 

 waters are not very large, however, as shown 

 by Potter and Baker (1956). Most of the 

 species isolated appear to be largely mem- 

 bers of the genus Micromonospom. These or- 

 ganisms produce on the plates hard colonies 

 pigmented orange to pink, and lacking the 

 typical aerial mycelium of the Streptomyces. 



The Micromonospora group was also found 

 in great abundance in the bottom deposits 

 of Wisconsin lakes, especially in profundal 

 zones rich in organic matter. Their abun- 

 dance as related to the bacteria found in the 

 same samples varied from 2.9 to 48.5 per 

 cent with an av^erage of 13.4 per cent. The 

 southern lakes showed larger numbers than 

 the northern lakes. The lake waters had only 

 negligible numbers of micromonosporas un- 

 less the bottom deposits had been agitated 

 and the organisms distributed through the 

 overlying water layers. Vertical distribution 

 through the bottom cores showed a decrease 

 in numbers as one proceeded downward. The 

 soils adjacent to the lakes had a few micro- 

 monosporas, but large numbers of strepto- 

 myces (Colmer and McCoy, 1943). 



Umbreit and McCoy reported that 10 to 

 20 per cent of the total microbial j^opulation 

 of the water comprise micromonosporas. At 

 times they made up 40 to 50 per cent of the 

 total numbers of colonies developing on the 

 plate. Th{> same was found to be true of the 

 lake nnid bottoms. In some cases as many 

 as 100, 000 cells of micromonospora were 



