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Marine Microbiology 



acids described above were more or less seriously required by 

 this microorganism for its normal growth. 



These experiments have also led to the development of the 

 minimum synthetic medium, for supporting the normal growth 

 of the organism, which had the composition as illustrated in 

 Table 5. 



TABLE 5 



Composition of Chemically Defined Medium for D. Desulfuricans 



(Maizuru 1) 



RESPONSE OF OTHER STRAINS OF DESULFOVIBRIO 

 DESULFURICANS TO ATP AND AMINO ACIDS 



To ascertain whether the nutritional pattern thus obtained 

 with the organism is applicable to other strains, we observed 

 subsequently this growth of several representative strains of this 

 species including both salt-water types and fresh-water types 

 in the above described defined medium (in the cases of fresh- 

 water strains NaCl as an ingredient was reduced to 5.0 g/L). 

 For reference, the growth of these microorganisms in the media 

 which contained, as nitrogen sources, peptone or Casamino acids 

 or eighteen amino acids in place of the thirteen amino acids was 

 also observed. The results of this experiment, which were given in 

 Table 6, indicate that all the strains tested grew well in the 

 medium containing the eighteen amino acids, although tlie growth 

 maxima obtained in this case were somewhat lower, in general, 

 than those in the medium based on peptone. In the medium con- 

 taining the thirteen amino acids, however, the growth of strains 

 Wandle, Hildenborough, Miyazaki, and El Agheila Z were dras- 



