486 



PRINCIPLES OF SOIL MICROBIOLOGY 



The choline is decomposed into ammonia, trimethylamine, carbon 



/ / CH 2 -CO\ 



dioxide and methane. Betaine I (CH 3 ) 3 = N X / J, creatinine, 



V XT / 



guanidine 41 and purine bases, like uric acid, also undergo decomposition 

 by microorganisms: 



NH 



HN - CO 



.A i- 



NH 



N C - N 



Guanine 





NH 2 



I 

 CH + 2 H 2 + 2 0-2 = C-NH + 3 C0 2 + CO(NH,), 



NH 2 

 Guanidine 



Urea 



Uric acid undergoes a series of transformations before ammonia is 

 produced, both in animal metabolism, and in its decomposition by 

 bacteria. 42 



HN - CO 



OC C - Is 



HN - C - NH 



Uric acid 



\ 



( 



/ 



CO + H 2 + K0 2 ) -» C0 2 + 



H 2 N 



OC CO - NH 



\ + 2 H,0 



CO .-► 



HN - CH - NH 



allantoin 



NH 2 



?° H +2 CO 7 + 2 H 2 Q + § (0 2 ) 

 COOH \ ~* 



NH 2 

 glyoxalic urea 



acid 



COOH 



COOH + 2 C0 2 + 4 NH, 

 oxalic acid 



41 Bierema, S. Die Assimilation von Ammon-, Nitrat- and Amidostickstoff 

 durch Mikroorganismen. Centralb. Bakt. II, 23: 672-726. 1909. 



42 Wiechowski, W. Das Schicksal intermediarer Harnsaure beim Menschen 

 und der Allantoingehalt des menschlichen Harns, nebst Bemerkungen uber 

 Nachweis und Zersetzbarkeit des Allantoins. Biochem. Ztschr., 25: 431-459. 

 1910; Liebert, F. The decomposition of uric acid by bacteria. K. Akad. 

 Wetensch. Amsterdam. Proc. Sect. Sci., 12: 54-64. 1909. 



