IV. BIOCHEMICAL SYSTEMS 345 



(which probably has the configuration of m?/o-inositoP^) stimulates the 

 respiration of rat brain homogenates/'' The hexamethyl ether of myo- 

 inositol produces convulsions in rabbits similar to those produced by 

 7-hexachlorocyclohexane; however, the ether is only 1/100 as active as the 

 chlorine-containing analog.'*^ 



Several workers^^- ^^ consider it likely that the biological antagonism 

 between hexachloroxycyclohexane and m?/o-inositol is actually exerted be- 

 tween the former and a bound or complex form of the latter. Since the 

 hexachlorocyclohexanes are much more soluble in fat solvents than in 

 aqueous systems, it is possible that they exert their effect on systems re- 

 acting ^^ith phospholipids containing mi/o-inositol. 



Some 3^ears ago Williams and coworkers^^ found relatively high concen- 

 trations (0.4 %) of inositol in a partially purified preparation of a-amylase 

 from pancreas. This led Lane and Williams*^ to test the effect of 7-hexa- 

 ehlorocyclohexane on the catalytic activity of the enzyme. Their report 

 that the chlorine-containing analog inhibited the enzyme and that ynyo- 

 inositol competitively reversed the inhibition could not be confirmed by 

 two groups^^' ^^ who used the more purified and crystalline enzyme. 



2. Bound Forms of m?/o-lNosiTOL 



Although there are appreciable quantities of free m?/o-inositol in many 

 biological materials, by far the greater part of this substance exists in 

 various complex forms. The more common materials with which it com- 

 bines include phosphate, proteins, fatty acids, glycerol, and galactose. 

 Although these complex compounds may be considered "structural ma- 

 terial" of the cell, they may be expected to have specific biocatalytic 

 functions as well. 



a. Inositol-Containing Phospholipids 



The phosphatides of the tubercle bacillus,^^- ''^ the soybean,**' *^ cotton 

 seed,^" and brain*^- ^" and liver^^ tissue contain inositol. Inositol mono- 



39 O. Bastiansen, 0. Ellefson, and O. Hassel, Research 2, 248 (1949). 



*o B. P. McNamara and S. Krop, Science 109, 330 (1949). 



*^ N. P. Buu-Hoi, E. Philippot, M. J. Dallemagne, and M. A. Gerebtzoff, Cotnpt. rend. 



soc. biol. 144, 1568 (1950). 

 " R. J. Williams, F. Schlenk, and M. A. Eppright, J. Am. Chem. Soc. 66, 896 (1944). 

 " R. L. Lane and R. J. Williams, Arch. Biochem. 19, 329 (1948). 

 ^^ E. H. Fischer and P. Bernfeld, Helv. Chim. Acta 32, 1146 (1949). 

 « S. Schwimmer and A. K. Balls, J. Biol. Chem. 179, 1063 (1949). 

 ^« R. J. Anderson, /. Am. Chem. Soc. 52, 1607 (1930) [C. A. 24, 2490 (19.30)] 

 " J. Cason and R. J. Anderson, J. Biol. Chem. 126, 527 (1938). 

 *» E. Klenk and R. Sakai, Hoppe-Seyler's Z. physiol. Chem. 258, 33 (1939). 

 " D. W. Woolley, J. Biol. Chem. 147, 581 (1943). 

 6" H. S. Olcott, Science 100, 226 (1944). 



