308 



BACTERIOLOGICAL CHEMISTRY 



has been shown to be identical with ochracin, produced 

 by A . melleus and A . ochraceus is a lactone of 6-hydroxy- 

 2-(a-hydroxypropyl) benzoic acid, 



OH 



which, on fusion with potassium hydroxide, yields 6- 



methyl salicylic acid. 



OH 



/^COOH 



"CH3 



, Avhich is a product of 



P. griseo-fulvum ; terrein, which is obtained from 

 A. terreus and has the structure, 4-propenyl-2-hydroxy- 

 3 : 5-oxidoc2/c?opentane-l-one 



CO 



HC 



CH.CH- 



HCOH 



-CH 



palitantin, C14H22O4, is a colourless, crystalline, unsaturated 

 dihydroxy aldehyde formed by P. palitans. 



It has been noted that in many cases the same products 

 may be produced from several sugars, including those with 

 fewer carbon atoms, besides glucose as carbon source. 

 This suggests, as has been pointed out above, that they 

 are synthesised from either a common simple intermediate, 

 possibly acetaldehyde, or else from a common reserve 

 carbohydrate which is formed irrespective of the sugar 

 with which the organism is supplied ; this may be 

 represented schematically in the case of a pentose as : — 



Pentose > Reserve Carbohydrate — ^-^ 5 Hexose > Other Products. 



