Yang, Hao. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 53-57). / Abstract also in Chinese. / Title Page --- p.i / Thesis Committee --- p.ii / Abstract (English version) --- p.iv / Abstract (Chinese version) --- p.vi / Acknowledgment --- p.vii / Table of Contents --- p.viii / List of Tables --- p.xi / List of Figures --- p.xii / List of Abbreviations and Symbols --- p.xv / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- DNA Methylation --- p.1 / Chapter 1.2 --- DNA Methylation Repair --- p.2 / Chapter 1.3 --- Objectives of This Work --- p.2 / Chapter 1.4 --- DNA Structure --- p.3 / Chapter 1.4.1 --- Nomenclature Scheme for DNA --- p.3 / Chapter 1.4.2 --- Base Pair Scheme --- p.4 / Chapter 1.4.3 --- Sugar Conformation --- p.5 / Chapter 1.4.4 --- Backbone Conformation --- p.5 / Chapter 2 --- Materials and Methods --- p.7 / Chapter 2.1 --- Sample Design --- p.7 / Chapter 2.2 --- Sample Preparation --- p.7 / Chapter 2.3 --- UV Optical Melting Study --- p.8 / Chapter 2.4 --- NMR Study --- p.9 / Chapter 2.4.1 --- NMR Melting Study --- p.10 / Chapter 2.4.2 --- Resonance Assignment --- p.10 / Chapter 2.4.3 --- Determination of Sugar Conformation --- p.12 / Chapter 2.4.4 --- Determination of Backbone Conformation --- p.13 / Chapter 3 --- Effect of 1-Methyladenine on Double-Helical DNA Structures --- p.14 / Chapter 3.1 --- NMR Resonance Assignments --- p.14 / Chapter 3.1.1 --- TA-oligo Resonance Assignments --- p.14 / Chapter 3.1.2 --- TmlA-oligo Resonance Assignments --- p.16 / Chapter 3.2 --- DNA Double-Helical Structures upon 1-Methylation of Adenine --- p.18 / Chapter 3.2.1 --- Base Pairing Mode --- p.18 / Chapter 3.2.2 --- Sugar Puker --- p.21 / Chapter 3.2.3 --- Backbone Conformation --- p.22 / Chapter 3.3 --- Summary --- p.24 / Chapter 4 --- Effect of 1-Methyladenine on Double-Helical DNA Stabilities --- p.25 / Chapter 4.1 --- Thermodynamic Studies --- p.26 / Chapter 4.1.1 --- Influence of m6A on UV Melting Studies --- p.26 / Chapter 4.1.2 --- Thermodynamics by NMR Melting Studies --- p.28 / Chapter 4.2 --- "NMR Structural Studies on Gm1A-, Am1A- and Cm1A-oligo" --- p.33 / Chapter 4.2.1 --- Gml A-oligo --- p.33 / Chapter 4.2.1.1 --- Gm1A-oligo Resonance Assignments --- p.33 / Chapter 4.2.1.2 --- Base Pair Structures of Gm1A-oligo --- p.35 / Chapter 4.2.2 --- AmiA-oligo --- p.37 / Chapter 4.2.2.1 --- Am1A-oligo Resonance Assignments --- p.37 / Chapter 4.2.2.2 --- Base Pair Structures of Am1A-oligo --- p.39 / Chapter 4.2.3 --- Cm1A-oligo --- p.43 / Chapter 4.2.3.1 --- Cm1A-oligo Resonance Assignments --- p.43 / Chapter 4.2.3.2 --- Base Pair Structures of Cm1A-oligo --- p.45 / Chapter 4.3 --- Summary --- p.46 / Chapter 5 --- Conclusion and Future work --- p.47 / Appendix I Proton chemical shift values of TA-oligo --- p.48 / Appendix II Proton chemical shift values of TmlA-oligo --- p.49 / Appendix III Proton chemical shift values of GmlA-oligo --- p.50 / Appendix IV Proton chemical shift values of Am1A-oligo --- p.51 / Appendix V Proton chemical shift values of CmlA-oligo --- p.52 / References --- p.53