150 PROVISION OF energy: oxidation 



H OH 



I I 



HOCH2 — C — C — is not attacked. Glycerol is oxidised to 



I I 

 OH H 



H H H 



I I I 

 dihydroxyacetone HOCHg— C — CH > HOCH2— C— CH 



II II I 

 OH OH OH 



A strain of Acetobacter is used to oxidise sorbitol to sorbose 

 as one of the steps in the commercial synthesis of vitamin C. 



H OH H H H OH H 



I I I I III 



HOCHj-C-C-C-C-CHpOH >- H0CH2-C-C-C-C-CH,0H 



I I I I I I I II 



OH H OH OH OH H OH . H 



SORBITOL ^-SORBOSE ^ ^i/J OvCHzOH 



HO ^ [^ OH 



H OH 



OXIDATION OF ALCOHOL BY ESCH. COLI 



In the case of the oxidation of ethyl alcohol by Esch. coli 

 the enzyme system has been analysed and the various 

 components identified. The alcohol is oxidised to acetalde- 

 hyde in the first place: 



CH3.CH2OH + > CH3.CHO + H2O . . . . (1) 



The enzyme concerned is alcohol dehydrogenase which 

 transfers hydrogen from alcohol to coenzyme I, 



Alcohol 



CH3 . CHgOH + coenzyme I > 



dehydrogenase 



CH3.CHO + reduced co. I (2) 



Keduced coenzyme then reacts with the cytochrome system 



