366 INOSITOLS 



No other natural antivitamins of inositol have been found. ?n?/o-Inositol 

 has been reported" to reverse the inhibitory effect of malonate on Clos- 

 tridium saccharohutyricum, whereas the d- and L-inositols do not. However, 

 borate also reversed the malonate inhibition, so a specific inhibition of 

 inositol by malonate was probably not involved. 



IX. Effects of Deficiency 



A. IN MICROORGANISMS 



E. E. SNELL 

 The physiological activity of inositol was first discovered by Eastcott,^ 

 who showed that the substance was required for growth of a strain of 

 yeast. Since these initial observations, many yeasts have been shown to be 

 stimulated by it; for 15 of 163 strains investigated by Burkholder et at} 

 inositol was essential for growth. Several fungi are known that require the 

 vitamin, e.g., Nematospora gossypii,^' ^ Lophodermium pinastri,^ and others. 

 Mutants of Neurospora crassa that require it have also been produced.^ 

 In all such organisms, growth increases with the inositol concentration 

 over a definite range of concentrations below the optimum ; microbiological 

 assay methods for inositol depend upon this fact.^ Although the vitamin 

 is required for growth of these microorganisms, nothing is known of the 

 essential metabolic role played by it; no distinctive metabolic aberrations 

 due to its lack have been reported. Presumably, in these organisms as in 

 higher plants and animals, inositol may be required for the formation of 

 essential lipid components of the cell;'^' ^ this, however, is mere speculation. 

 It is a striking fact that no bacteria have so far been reported to require 

 inositol, and it is not certain whether inositol is present at all in some bac- 

 teria, e.g., Escherichia coli.^ Other bacteria, e.g., the tubercle bacillus, are 

 known to contain it.^" Indeed, the occurrence of inositol in the phosphatide 



" A. J. Rosenberg, Compt. rend. soc. biol. 142, 443 (1948). 



1 E. V. Eastcott, /. Phys. Chem. 32, 1094 (1928). 



2 P. R. Burkholder, I. McVeigh, and D. Moyer, /. Bacteriol. 48, 385 (1944). 



3 H. W. Buston and B. N. Pramanik, Biochem. J. (London) 25, 1656 (1931). 

 ^ F. Kogl and N. Fries, H oppe-Seyler' s Z. physiol. Chem. 249, 93 (1937). 



6 G. W. Beadle and E. L. Tatum, Am. J. Botany 32, 678 (1945). 



6 E. E. Snell in P. Gyorgy, Vitamin Methods, Vol. I, p. 327, Academic Press, New 

 York, 1950. 



7 I. Rhymer, G. I. Wallace, L. W. Byers, and H. E. Carter, /. Biol. Chem. 169, 457 

 (1947). 



8 D. W. Woolley, /. Biol. Chem. 147, 581 (1943). 

 3 D. W. Woolley, /. Exptl. Med. 75, 277 (1942). 



10 R. J. Anderson, /. Am. Chem. Soc. 52, 1607 (1930). 



