264 G. R. WYATT 



for aldoses, including ribose and deoxyribose, but not for ketoses; increased 

 range of sensitivity is reported for aniline hydrogen phosphate. ^"^ The re- 

 agents mentioned earlier (Section III. 2) for ribosides and deoxy ribosides 

 react also with the free sugars. 



The Rf values of the pentoses, along with rhamnose and 2-deoxyribose, 

 in several chromatographic solvents are shown in Table V. Improved sepa- 

 rations of a number of sugars are reported by Jermyn and Isherwood^"^ 

 using ethyl acetate-pyridine-water (2:1:2) and ethyl acetate-acetic acid- 

 water (3:1:3) as solvents ; however, Rp values of ribose and deoxyribose 

 were not determined. 2-Deoxyribose, 3-deoxyribose, and 4-deoxyribose are 

 separable with a butanol-ethanol mixture. ^"^ The d- and L-isomers of sugars 

 have not been separated on paper chromatograms. 



The purine-bound sugar from pentose nucleic acids may be liberated by 

 hydrolysis in N H2SO4 at 100° for 1 hour,^^ and the hydrolysate can be 

 applied to paper for chromatography without removal of the acid.^"^ From 

 DNA, because of the lability of the sugar and the stability of the inter- 

 nucleotide linkages, enzymic hydrolysis is required: Chargaff et al}°^ used 

 deoxyribonuclease together with a phosphatase derived from Aspergillus 

 to give nucleosides, after which the purine nucleosides were split by heating 

 at pH 1.5 to 100° for 12 minutes. 



The sugar components of all pentose nucleic acids yet examined by these 

 methods have proved to be chromatographically identical with ribose, and 

 those of deoxypentose nucleic acids, with 2-deoxyribose. [Cf. Chapters 2, 

 10, and 11.] 



VII. Addendum 



The following reports have appeared, or have come to the writer's atten- 

 tion, since preparation of this chapter. 



A solvent composed of 7 vol. 95 % ethanol plus 3 vol. M ammonium ace- 

 tate buffer of pH 3.8, used in the study of uridine diphosphate glucose, 

 gives fair resolution of the nucleotides of PNA.^°^ Several systems suitable 

 for resolution of deoxyribosides have been described by Tamm et alJ''^"- Cald- 

 welP°^ has demonstrated resolution of adenosine-5 '-phosphate, diphosphate, 

 and triphosphate with Hanes and Isherwood's solvent containing 60 cc. 



1"! N Aniline in butanol, 1 vol., mixed with 2 A'^ HjPO* in butanol, 2 vol.; J. L. Bryson 



and T. J. Mitchell, Natxire 167, 864 (1951). 

 "2 M. A. Jermyn and F. A. Isherwood, Biochem. J. 44, 402 (1949). 

 103 p. Y. V. Ward and P. W. Kent, Nature 170, 936 (1952). 

 10^ B. D. E. Gaillard, Nature 171, 1160 (1953). 

 ifts E. Chargaff, E. Vischer, R. Doniger, C. Green, and F. Misani, J. Biol. Chem. 177, 



405 (1949). 

 los A. C. Paladini and L. F. Leloir, Biochem. J. 51, 426 (1952). 

 1" P. C. Caldwell, Biochem. J. 55, 458 (1953). 



