354 INOSITOLS 



It will be noted that in every case it was the "pole" hydroxyl groups which 

 were oxidized by Acetobacter suboxydans. Another organism, Aerobacter 

 aerogenes, has also been found to oxidize the polar hydroxyl group of myo- 

 inositol}'^ It has not yet been determined whether the relationship between 

 the polar and the equatorial groups is also a factor in the vitamin activity 

 of inositol for various organisms. 



VI. Biogenesis 



ARTHUR H. LIVERMORE 



That plant tissues can synthesize inositol is evident; that animal tissues 

 can do so has not yet been established. Increases in the inositol content of 

 animal tissues may represent synthesis by intestinal flora rather than 

 synthesis by the animal body itself. Increases in the inositol content of 

 plant tissues, on the other hand, can be accounted for only by synthesis 

 in the plant tissues. The mechanism of this synthesis has not yet been 

 demonstrated, but present evidence implicates the sugars, and particularly 

 glucose, as the precursors of inositol. Fischer ^ has suggested that 



... it could be deduced from chemical evidence . . . that inositol is most likely an 

 intermediate between carbohydrates and aromatic substances; moreover it very 

 likely serves as a reserve carbohydrate, storing away glucose in a form which could 

 be easily mobilized. Finally, there is the speculative possibility that inositol could 

 act as an intermediate enabling the easy transformation of one hexose into another. 



Fischer also presented chemical evidence to support his suggestion that 

 inositol may be synthesized from glucose in biological tissues. 



A. INOSITOL SYNTHESIS BY MICROORGANISMS 



The presence of inositol in the phosphatides of the tubercle bacillus was 

 first reported in 1930.^ The ability of two strains of this bacillus to synthe- 

 size inositoP indicates that the tubercle bacillus need not be dependent upon 

 the host for a supply of this vitamin. The synthesis of inositol by other 

 bacteria, grown in vitamin-free media, has also been demonstrated.^- ^ 

 The amounts synthesized were indicated by the observation^ that various 



12 B. Magasanik, J. Am. Chem. Soc. 73, 5919 (1951). 



1 H. O. L. Fischer, Harvey Lectures 40, 156 (1945). 



2 R. J. Anderson and E. G. Roberts, J. Biol. Chem. 89, 599, 611 (1930). 



3 H. Pope and D. T. Smith, Am. Rev. Tuberc. 54, 559 (1946) [C. A. 42, 3017 (1948)]. 

 * R. C. Thompson, Univ. Texas Publ. 4237, 87 (1942). 



6 L. W. Jones and J. E. Greaves, Soil Sci. 55, 393 (1943) [C. A. 37, 6300 (1943)]. 



