Pfizer Handbook of Microbial Metabolites 



i6 



Coenzyme A 



SH 



I 

 CH2— CH2— CH(CH2)4COOH 



Dihydroiipoic Acid 



CH3CO — Coenzyme A 



The nature of the actual catalysis of pyruvate decarboxyla- 

 tion and of aldol condensations by thiamine pyrophosphate co- 

 enzyme has been elucidated.^ It is shown below : 



NH2 



// 



Thiamine 



Pyrophosphate 

 Chloride 



CH3 



O O 



CH2— N' I t T 



<S^=^CH2— CH2— O— P— O— P— OH 



CHa 



^.e 



e, 



OH 



CH3— c— cooQ 



OH 







@/^S -H® ®/^~S CH3— C— COO0 ©/^S -CO2 



R— N I »R— N; I >R— N/ ' 



OH 



CHi 



R— N 



/~s 



O OH 



CH3— C— C— 



— C— 



* Ronald Breslow, Chem. and Ind., 893 (1957). 



