500 V. CHEMISTRY OF PHOSPHATIDES AND CEREBROSIDES 



cause of its conversion to mucic acid and because it forms the expected 

 hydrazone. The presence of c?(+)-galactose in pyranose form has been 

 proved by Pryde and Humphreys. ^^^ As discussed earher, it is known that 

 the galactose is combined in glucosidic Hnkage with sphingosine through 

 one of the hydroxy 1 groups of the base. 



The discovery that ghicose-containing cerebrosides, also, may occur re- 

 sulted from a study of the composition of the cerebroside which is deposited 

 in the spleen in Gaucher's disease. Halliday, Deuel, Tragerman, and 

 Ward^^" found that the sugar obtained by the hydrolysis of cerasine pre- 

 pared from a Gaucher spleen is completely fermentable by yeast, in con- 

 trast to the non-fermentability of the sugar fraction from the brain cerebro- 

 side. It was further shown that the osazone is identical with glucosazone. 

 In fact, the application of bacteriological tests to differentiate among 

 mannose, fructose, and glucose (all of which are fermentable with yeast 

 and yield glucosazone) proved that the component sugar was glucose. The 

 presence of glucose in the Gaucher spleen was later confirmed by Klenk 

 and Rennkamp,^*'*''^" Danielson, Hall, and Everett, ^"^^ and others. ^^^ 

 Two new cerebroside preparations from Gaucher spleens recently examined 

 in the author's laboratory have also been shouii to contain glucose. One 

 may conclude that the glucose-containing cerebroside is the form most 

 frequently found when abnormal deposits of cerebrosides occur in the 

 spleen. However, the data of Lieb/^** as well as those of Lieb and Mladen- 

 ovic*^^ based upon studies made many years ago on the sugar component 

 of the spleen cerebroside, are quite definite in proving the carbohydrate to 

 be galactose. A re-examination of the same material made later by Lieb''^'^ 

 has again demonstrated that galactose is the component sugar.'*''' It 

 would therefore seem probable that two types of cerebroside may be laid 

 down in Gaucher's disease — the galactose-containing type and the glucose- 

 containing one. This view is also held by Klenk and Rennkamp,*" who 

 believe that the latter type is much more common. All samples of glucose 

 cerebrosides reported to date have been of the cerasine type. 



The question which naturally arises is whether the glucose cerebroside 

 occurs only under abnormal conditions attendant upon Gaucher's disease, 

 or whether it actually may be classed as a normal cell constituent. Klenk 

 and Rennkamp^'^^ have shown that the second possibility is the correct one, 



^6" E. Klenk and F. Rennkamp, Z. physwl. Chem., 267, 128-144 (1940). 



*" E. Klenk and F. Rennkamp, Z. physiol. Chem., 272, 280-282 (1942). 



«8 I. S. Danielson, C. H. Hall, and M. R. Everett, Proc. Soc. Expll. Biol. Med., 49, 

 569-571 (1942). 



«9 Aghion, "La Maladie de Gaucher dans I'enfanee," Thesis, Paris, 1934. Cited by 

 E. Klenk and F. Rennkamp, Z. physiol. Chem., 273, 253 (1942). 



^'» H. Lieb, Z. physiol. Chem., 170, G0-G7 (1927). 



^'1 H. Lieb and V. Giinther, Z. physiol. Chem., 271, 211-213 (1941). 



«2 E. Klenk and F. Rennkamp, Z. physiol. Chem., 273, 253-208 (1942). 



