X CONTENTS 



7. Separation of Nucleic Acid Components by Chromatography on Filter Paper 



BY G. R. Wyatt 243 



I . Introduction 243 



II. General Technique of Paper Chromatography 244 



III. Detection of Purine and Pyrimidine Derivatives on Filter Paper 245 



IV. Solvent Systems 248 



V. Quantitative Estimation of the Nitrogenous Components of Nucleic 



Acids 257 



VI. Chromatography of Nucleic Acid Sugars 263 



VII. Addendum 264 



8. The Electrophoretic Separation of Nucleic Acid Components by J. D. Smith 267 



I. Theory of the Electrophoretic Separation of Nucleic Acid Components 267 



II. Apparatus and Techniques 274 



III. Applications of the Method 276 



9. Color Reactions of Nucleic Acid Components by Zacharias Dische 285 



I. Color Reactions of Nucleic Acids and their Constituents Based on Re- 

 actions of Their Sugars 286 



II. Determination of Purine and Pyrimidine Bases of Nucleic Acids by 

 Characteristic Color Reactions 303 



10. Isolation and Composition of the Deoxypentose Nucleic Acids and of the 

 Corresponding Nucleoproteins by Erwin Chargaff 307 



I. Introductory Remarks 308 



II. Deoxypentose Nucleoproteins 309 



III. Isolation of Deoxypentose Nucleic Acids 321 



IV. Properties of Deoxypentose Nucleic Acids 333 



V. Some Partial Degradation Products 340 



VI. Constituents of Deoxypentose Nucleic Acids 345 



VII. Composition of Deoxypentose Nucleic Acids 348 



VIII. Fractionation of Deoxypentose Nucleic Acids , . 358 



IX. Composition Studies and Structural Investigations 366 



X. Correlations and Concluding Remarks 368 



11. Isolation and Composition of the Pentose Nucleic Acids and of the Corre- 

 sponding Nucleoproteins by B. Magasanik 373 



I . Introduction 373 



II. Isolation of Pentose Nucleoproteins 374 



III. The Nature of Pentose Nucleoprotein 379 



IV. The Isolation of Pentose Nucleic Acids 384 



V. The Nature of PNA •. 391 



VI. The Nucleotide Composition of PNA 394 



12. Evidence on the Nature of the Chemical Bonds in Nucleic Acids by D. M. 

 Brown and A. R. Todd 409 



I. Introduction 409 



II. Chemistry of the Ribonucleic Acids 413 



III. Structure of the Deoxyribonucleic Acids 439 



