Pfizer Handbook of Microbial Metabolites 484 



Virtually nothing is known concerning the biogenesis of 

 pyridoxine. Since catabohsm often furnishes clues useful 

 in the study of biosynthesis, it should be noted that oxida- 

 tive bacteria degrade pyridoxine as follows : ^* 



CH2OH 



CH2OH CH2OH 



HO I ' CH2OH HO I CHO HO COOH 



CH3' CH3 CH3 



Pyridoxine Isopyridoxal 5-Pyridoxic Acid 



(Pyridoxol) (Lactone) 



CH2-O 



HO ' ^ 



O 



CH3 



i 



18 Victor W. Rodwell, Benjamin E. Volcani, Miyoshi Ikawa and 

 Esmond E. Snell, /. Biol. Chem. 233 1548 (1958); Miyoshi Ikawa, 

 Victor W. RodweU and Esmond E. SneU, ibid. 233 1555 (1958). 



