by Tang Wai Kwan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 91-110). / Abstracts in English and Chinese. / Acknowledgements / 論文摘要 / Abstract / Abbreviations / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Aldehyde Dehydrogenase Extended Family --- p.1 / Chapter 1.1.1 --- Phylogenetic Tree --- p.2 / Chapter 1.1.2 --- Physiological Functions --- p.4 / Chapter 1.1.3 --- Structural Conservations --- p.7 / Chapter 1.2 --- ALDH-1 and ALDH-2 --- p.9 / Chapter 1.3 --- Antiquitin --- p.11 / Chapter 1.4 --- Osmoregulation --- p.14 / Chapter 1.4.1 --- Osmoprotectant --- p.14 / Chapter 1.4.2 --- Betaine Aldehyde Dehydrogenase --- p.15 / Chapter 1.5 --- Objectives of the Present Study --- p.18 / Chapter Chapter 2 --- Purification and Characterization of Seabream ALDH-2 and Antiquitin --- p.20 / Chapter 2.1 --- Introduction --- p.20 / Chapter 2.2 --- Materials --- p.21 / Chapter 2.3 --- Methodology / Chapter 2.3.1 --- Preparation of Crude Tissue Extract --- p.22 / Chapter 2.3.2 --- Synthesis of α-Cyanocinnamate Sepharose --- p.22 / Chapter 2.3.3 --- Synthesis of p-Hydroxyacetophenone Sepharose --- p.23 / Chapter 2.3.4 --- Purification of ALDH-2 --- p.23 / Chapter 2.3.5 --- Purification of Antiquitin --- p.24 / Chapter 2.3.6 --- Enzyme and Protein Assays --- p.24 / Chapter 2.3.7 --- Electrophoretic Procedures / Chapter 2.3.7.1 --- Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE) --- p.26 / Chapter 2.3.7.2 --- Native PAGE --- p.27 / Chapter 2.3.7.3 --- Isoelectric focusing (IEF) --- p.27 / Chapter 2.3.8 --- N-terminal Amino Acid Sequencing --- p.28 / Chapter 2.4 --- Results / Chapter 2.4.1 --- Tissue Distribution of ALDH --- p.29 / Chapter 2.4.2 --- Purification and Molecular Properties of ALDH-2 --- p.31 / Chapter 2.4.3 --- Kinetic Properties of ALDH-2 --- p.42 / Chapter 2.4.4 --- Purification and Molecular Properties of Antiquitin --- p.49 / Chapter 2.4.5 --- Kinetic Properties of Antiquitin --- p.54 / Chapter Chapter 3 --- Discussion / Chapter 3.1 --- Tissue Distribution --- p.66 / Chapter 3.2 --- N-terminal Amino Acid Sequencing --- p.67 / Chapter 3.3 --- Purification of Seabream ALDH --- p.68 / Chapter 3.3.1 --- Separation of Two ALDH isoforms --- p.69 / Chapter 3.3.2 --- Binding Affinity of α-Cyanocinnamate Sepharose --- p.70 / Chapter 3.3.3 --- Purification --- p.72 / Chapter 3.4 --- Electrophoretic Properties --- p.73 / Chapter 3.5 --- pH and Temperature Stability --- p.74 / Chapter 3.6 --- Substrate Specificity --- p.77 / Chapter 3.7 --- Possible Functions of Antiquitin --- p.80 / Chapter 3.8 --- Future Prospects --- p.84 / Chapter Chapter 4 --- Conclusion --- p.90 / Chapter Chapter 5 --- References --- p.91