170 



A. N. BELOZERSKY AND A. S. SPIRIN 



TABLE IV 

 DNA Composition of Bacteria (Gram-Positive and Gram-Negative Cocci) 



Species 



Base proportions 



(moles %) 



G 



(' 



A + T 

 G + C 



Gram 



S3 



Sarcina lutea 



Sarcina lutea 



Sarcina lutea 



Micrococcus iysodeikticus 



Sarcina fiava 



Neisseria meningitidis 



Neisseria gonorrhoeae 



Diplococcus pneumoniae type III 



Veillonella parvula 



Streptococcus faecalis ("bound DNA") 



Streptococcus faecalis ("free DNA") 



Streptococcus faecalis (group D) 



Streptococcus foelidus 



Streptococcus pyogenes (group A) 



Streptococcus zymogenes (group D) 



Micrococcus asaccharolyticus 



Micrococcus (Staphylococcus) aureus 



SAB 

 Micrococcus (Staphylococcus) aureus 



209 P 

 Micrococcus pyogenes (Staphylococcus 



aureus) 

 Micrococcus pyogenes Oxf. 

 Micrococcus pyogenes 1161 

 Micrococcus pyogenes 1149 

 Micrococcus pyogenes 145 

 Micrococcus pyogenes m 320 

 Staphylococcus epidermidis 



37.1 

 36.4 

 32.4 

 37.3 

 33.5 

 25.5 

 25.2 

 20.5 

 18.5 

 18.3 

 16.5 

 16.9 

 16.8 

 16.6 

 16.2 

 18.8 

 21.0 



13.4 

 13.6 

 18.7 

 14.4 

 15.6 

 24.6 

 25.3 

 29.8 

 31.7 

 29.2 

 30.0 

 33.4 

 32.1 

 33.4 

 33.1 

 31.2 

 30.8 



37.1 

 35.6 

 31.5 

 34.6 

 35.1 

 25.0 

 24.4 

 18.0 

 18.0 

 20.3 

 21.0 

 17.7 

 16.8 

 17.0 

 17.4 

 15.3 

 19.0 



12.4 

 14.4 

 17.4 

 13.7 

 15.8 

 24.9 

 25.1 

 31.6 

 31.8 

 32.2 

 32.5 

 32.0 

 34.3 

 33.0 

 33.3 

 34.7 

 29.2 



0.35 

 0.39 

 0.56 

 0.39 

 0.46 

 1.00 

 1.01 

 1.59 

 1.74 

 1.59 

 1.67 

 1.89 

 1.97 

 1.97 

 1.97 

 1.91 

 1.50 



18.5 31.0 19.2 31.2 1.65 



17.3 32.3 17.4 33.0 1.1 



+ / 



+ 



References 

 11 S. K. Dutta et al., J. Gen. Microbiol. 14, 160 (1956). 

 b A. S. Spirin et al., Biokhimiya 22, 144 (1957). 

 c Ki Yong Lee et al., Ann. inst. Pasteur 91, 212 (1956). 

 d M. M. Daly et al., J. Gen. Physiol. 33, 497 (1950). 

 e H. S. Sherratt and A. J. Thomas, J. Gen. Microbiol. 8, 217 (1953). 

 ! B. W. Catlin and L. S. Cunningham, J. Gen. Microbiol. 19, 522 (1958). 



On inspection of Table I (gram-negative bacilli), it will be noticed that 

 the arrangement of the organisms in the order of increasing values of the 

 ratio (A -f T)/(G + C) may not be fortuitous from a systematic point of 

 view. As a matter of fact, with some exceptions, the species which have 

 been placed at the top of the table (species with the marked GC-type of 

 the DNA) represent such families as Pseudomonadaceae, Achromobacte- 

 riaceae, and Azotobacteriaceae. The bottom of the table (the marked AT- 



