Histidine-rich glycoprotein (HRG) is a plasma protein that regulates key cardiovascular processes such as coagulation, angiogenesis and immune response. The protein consists of six distinct functional domains: two N-terminal domains (N1 and N2), two proline-rich regions (PRR1 and PRR2), a central histidine-rich region (HRR) and a C-terminal domain. The HRR binds Zn²⁺, which alters the affinity of HRG towards various ligands including the anticoagulant, heparin. A key aim of this study was to structurally characterise HRG. The 1.93 Å crystal structure of the HRG N2 domain presented here represents the first crystallographic snapshot of the molecule. The N2 domain is cystatin-like and N-glycosylated at Asn184. An S-glutathionyl adduct was observed at Cys185, providing in vivo evidence that release of an anti-angiogenic HRR/PRR fragment is controlled in part by a redox mechanism, representing a novel further role for GSH in regulation of angiogenesis. Since Zn²⁺ regulates some of the functions of HRG, the dynamics of Zn²⁺ in plasma were investigated using a combination of ITC, ELISA and thrombin assay systems. Zn²⁺ is normally associated with albumin in circulation, but its ability to bind Zn²⁺ is allosterically inhibited upon fatty acids binding to albumin. Elevated plasma fatty acid levels are associated with some disease states. It is proposed that this may alter the proportion of Zn²⁺ bound to HRG, which could in turn activate thrombin to promote coagulation. These studies provide evidence to suggest that Zn²⁺-dependent activation of HRG (following fatty acid binding to albumin) may play a role in the development of haemostatic complications in susceptible individuals. Finally, the Zn²⁺ binding ability of albumin was probed in order to locate unidentified sites using recombinant albumin mutants. H9A, H67A, E252A, D256A and H288A mutants all exhibited diminished Zn²⁺ binding ability, indicating that these residues are involved directly or indirectly in Zn²⁺ binding.

Ellen Lai Ping Chan. / Thesis (Ph.D)--Chinese University of Hong Kong, 1990. / Bibliography: leaves 238-272. / Chapter CHAPTER I --- LITERATURE REVIEW / Chapter 1. --- History --- p.1 / Chapter 2. --- Species Distribution of BAT --- p.3 / Chapter 3. --- Distribution of BAT --- p.4 / Chapter 4. --- Structure of BAT --- p.4 / Chapter 4.1. --- Macroscopic Appearance --- p.4 / Chapter 4.1.1. --- Innervation --- p.4 / Chapter 4.1.2. --- Blood supply --- p.5 / Chapter 4.2. --- Microscopic Structure of BAT --- p.6 / Chapter 4.3. --- Difference Between Brown Fat and White Fat --- p.9 / Chapter 5. --- Composition of BAT --- p.11 / Chapter 6. --- The Mechanisms of Brown Adipose Tissue Thermogenesis --- p.12 / Chapter 6.1. --- Factors Influencing Proton Transport by UCP --- p.16 / Chapter 6.2. --- Postulated Sequence of Events during Thermogenesis --- p.18 / Chapter 7. --- Measurements of thermogenic Capacity of BAT --- p.21 / Chapter 8. --- Age-related Differences in BAT --- p.28 / Chapter 9. --- Non-shivering Thermogenesis and BAT --- p.32 / Chapter 9.1. --- Changes In BAT During Cold Acclimation --- p.35 / Chapter 9.1.1. --- GDP Binding --- p.35 / Chapter 9.1.2. --- Concentration of UCP --- p.37 / Chapter 9.1.3. --- Metabolic changes in BAT during Cold Acclimation --- p.39 / Chapter 10. --- Diet-induced Thermogenesis and BAT --- p.41 / Chapter 10.1. --- Mechanism of DIT --- p.42 / Chapter 10.2. --- Controversies in DIT --- p.44 / Chapter 10.3. --- Nutritional Factors Inducing DIT --- p.46 / Chapter 10.4. --- DIT in Man --- p.47 / Chapter 10.5. --- Neuroendocrine Control of BAT in DIT --- p.48 / Chapter 10.6. --- Effects of Fasting in BAT --- p.51 / Chapter 11. --- Obesity and BAT --- p.53 / Chapter 11.1. --- NST and DIT in Obese Animals --- p.58 / Chapter 11.2. --- Regulation of BAT in Obese Animals --- p.59 / Chapter 11.2.1. --- Sympathetic Nervous System in Obese Animals --- p.59 / Chapter 11.2.2. --- Corticosteriods in Obese Animals --- p.61 / Chapter 11.2.3. --- Adrenergic Receptors in Obese Animals --- p.63 / Chapter 11.2.4. --- Insulin in Obese Animals --- p.64 / Chapter 12. --- Pregnancy and Lactation and BAT --- p.67 / Chapter 12.1. --- Energy Balance During Pregnancy and Lactation --- p.67 / Chapter 12.2. --- Some Metabolic Changes During X Pregnancy and Lactation --- p.68 / Chapter 12.3. --- Role of BAT in Pregnancy and Lactation --- p.70 / Chapter 12.4. --- Mechanism of Regulation of Thermogenesis during Pregnancy and Lactation --- p.71 / Chapter 13. --- Factors Controlling the Thermogenesis --- p.75 / Chapter 13.1. --- Sympathetic Nervous Control --- p.75 / Chapter 13.1.1. --- Studies of Administration of Noradrenaline --- p.75 / Chapter 13.1.2. --- Control of the Fuel Supply to BAT by Sympathetic Nervous System --- p.77 / Chapter 13.1.3. --- Sympathetic denervation --- p.78 / Chapter 13.2. --- Hormonal Control --- p.79 / Chapter 13.2.1. --- Thyroid Hormone --- p.79 / Chapter 13.2.2. --- Insulin --- p.81 / Chapter 13.2.3. --- Pituitary Hormones --- p.83 / Chapter 13.2.4. --- Glucocorticoids --- p.83 / Chapter 13.2.5. --- Corticotropin-Releasing Factor --- p.85 / Chapter 14. --- Aims of the Study --- p.87 / Chapter CHAPTER II --- ISOLATION AND PURIFICATION OF UCP AND DEVELOPMENT OF AN ENZYME LINKED IMMUNOSORBENT ASSAY FOR UCP / Chapter 1. --- INTRODUCTION --- p.88 / Chapter 2. --- MATERIALS AND METHODS --- p.89 / Chapter 2.1. --- Animals --- p.89 / Chapter 2.2. --- Collection of BAT --- p.89 / Chapter 2.3. --- Isolation of Mitochondria --- p.90 / Chapter 2.4. --- Electron Microscopy (EM) of Isolated BAT Mitochondria --- p.92 / Chapter 2.5. --- Measurement of Protein and Cytochrome C Oxidase Activity --- p.94 / Chapter 2.5.1. --- Measurement of Protein Concentration --- p.94 / Chapter 2.5.2. --- Measurement of Cytochrome C Oxidase Activity --- p.99 / Chapter 2.6. --- GDP Binding Assay of BAT Mitochondria --- p.101 / Chapter 2.6.1. --- GDP Binding Assay of Mitochondria by Centrifugation Method --- p.103 / Chapter 2.6.2. --- GDP: Binding Activity by Equilibrium Dialysis --- p.106 / Chapter 2.6.3. --- GDP Binding by Microfiltration Method --- p.108 / Chapter 2.7. --- Experiments Designed for Validation of GDP Binding Assay --- p.109 / Chapter 2.7.1. --- GDP Binding Activity in BAT Mitochondria after Noradrenaline Treatment --- p.109 / Chapter 2.7.2. --- GDP Binding Activity in BAT Mitochondria after Cold Acclimation and Noradrenaline Treatment --- p.110 / Chapter 2.7.3. --- Effect of Food Restriction on Cold Acclimated Rats --- p.110 / Chapter 2.7.4. --- GDP Binding Activity of BAT Mitochondria of Rats of Different Ages --- p.111 / Chapter 2.8. --- Isolation and Purification of UCP --- p.111 / Chapter 2.9. --- Sodium Dodecyl Sulphate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) --- p.115 / Chapter 2.10. --- Methods for Raising Anti-Rat-UCP Antibody and the Characterization of Antiserum --- p.120 / Chapter 2.10.1. --- Raising Rabbit Anti-Rat-UCP Antibody --- p.120 / Chapter 2.10.2. --- Western Blot Analysis For Cross Reactivity Study --- p.120 / Chapter 2.10.3. --- Immuno-Autoradiographic Method for Detection of Specificity of Rabbit Anti-Rat UCP Antiserum --- p.121 / Chapter 2.11. --- Enzyme Linked Immunosorbent Assay For UCP --- p.124 / Chapter 2.12. --- Experiment Designed to Validate the ELISA --- p.129 / Chapter 2.13. --- Statistical Analysis --- p.129 / Chapter 3. --- RESULTS --- p.130 / Chapter 3.1. --- Electron Microscopy of Isolated BAT Mitochondria --- p.130 / Chapter 3.2. --- GDP Binding Assay of BAT Mitochondria --- p.130 / Chapter 3.3. --- Experiments Designed for Validation of GDP Binding Assay --- p.133 / Chapter 3.3.1. --- GDP Binding Activity of BAT Mitochondria after Noradrenaline Injection --- p.133 / Chapter 3.3.2. --- GDP Binding Activity of BAT Mitochondria after Cold Acclimation and Noradrenaline Treatment --- p.136 / Chapter 3.3.3. --- Effects of Food Restriction on Cold Acclimated Rats --- p.136 / Chapter 3.3.4. --- GDP Binding Activity of BAT Mitochondria from Rats of Different Ages --- p.140 / Chapter 3.4. --- Isolation and Purification of UCP --- p.140 / Chapter 3.4.1. --- Results of SDS-PAGE --- p.143 / Chapter 3.4.2. --- Results of GDP Binding Activity --- p.149 / Chapter 3.5. --- Rabbit Anti-rat-UCP Antibody and the Characterization of Antiserum --- p.151 / Chapter 3.5.1. --- Immuno-autoradiography for Specificity of Rabbit Anti-rat-UCP Antiserum --- p.153 / Chapter 3.5.1.1. --- Cross-reactivity of the Rabbit Anti-rat-UCP Antiserum to Mitochondrial Proteins of BAT and from other Tissues --- p.153 / Chapter 3.5.1.2. --- Cross-reactivity of the Rabbit Anti-rat-UCP Antiserum to BAT Mitochondrial Protein from Different Rodent Species --- p.156 / Chapter 3.5.1.3. --- Dose Response of Rabbit Anti-rat-UCP Antiserum to UCP --- p.159 / Chapter 3.6. --- ELISA of UCP --- p.161 / Chapter 3.6.1. --- Determination of Maximum Amount of UCP Binding on Microtitre Plate --- p.161 / Chapter 3.6.2. --- Antibody Dilution Curve --- p.161 / Chapter 3.6.3. --- Incubation Time for Enzyme-Substrate Reaction --- p.163 / Chapter 3.6.4. --- Competitive ELISA --- p.163 / Chapter 3.6.5. --- Precision of ELISA --- p.167 / Chapter 3.7. --- Experiment Designed for Validation of ELISA by Measuring UCP in Cold Acclimated Rats --- p.170 / Chapter 4. --- DISCUSSION --- p.172 / Chapter 4.1. --- GDP Binding Assay of BAT Mitochondria --- p.172 / Chapter 4.2. --- Isolation and Purification of UCP --- p.176 / Chapter 4.3. --- Development and Evaluation of ELISA --- p.178 / Chapter CHAPTER III --- CHANGES IN BAT DURING PREGNANCY AND LACTATION AND ROLE OF PROLACTIN / Chapter 1. --- INTRODUCTION --- p.184 / Chapter 2. --- MATERIALS AND METHODS --- p.187 / Chapter 2.1. --- Animal --- p.187 / Chapter 2.2. --- Experimental Designs --- p.187 / Chapter 2.2.1. --- "Effects of Pregnancy, Lactation and Post Weaning on BAT" --- p.187 / Chapter 2.2.2. --- Effect of Metoclopramide on BAT --- p.188 / Chapter 2.2.3. --- Effect of Metoclopramide and Bromocriptine on BAT --- p.188 / Chapter 2.2.4. --- Effect of PRL Injection on BAT --- p.189 / Chapter 2.2.5. --- Continuous infusion of PRL --- p.189 / Chapter 2.6.6. --- Measurements of BAT Parameters --- p.191 / Chapter 2.2.7. --- RIA of serrum PRL --- p.191 / Chapter 2.2.8. --- PRL Receptors in BAT --- p.197 / Chapter 2.4. --- Statistical Analysis --- p.201 / Chapter 3. --- RESULTS --- p.202 / Chapter 3.1. --- Effects of Pregnancy and Lactation --- p.202 / Chapter 3.1.1. --- Food Consumption and Body Weight --- p.202 / Chapter 3.1.2. --- BAT --- p.205 / Chapter 3.1.3. --- Serum PRL level --- p.209 / Chapter 3.2. --- Effects of PRL njection --- p.213 / Chapter 3.3. --- Effects of Continuous Infusion of PRL on BAT --- p.213 / Chapter 3.4. --- Effects of Metoclopramide on BAT --- p.216 / Chapter 3.5. --- Effects of Bromocriptine and Metoclopramide on BAT --- p.216 / Chapter 3.6. --- PRL Receptor in BAT --- p.219 / Chapter 4. --- DISCUSSION --- p.223 / GENERAL CONCLUSION --- p.236

隨著社會發展, 各種病毒、環境致癌物, 以及不健康食等多種因素導致諸種頑症高發, 並以人類獲得牲免疫缺陷綜合症(艾滋病)和各種腫瘤為代表。從天然產物, 特別是傳統中藥中, 篩選藥用有效成分是治療這類疾病的有效途徑之一。研究發現, 核糖體失活蛋白, 核糖核酸酶, 凝集素, 蛋白酪抑制劑等具有良好的藥用開發前景。本論文著重於從不同植物種于中篩選藥用蛋白, 並對其藥用機制進行研究。 / 是吹研究共純化出六種藥用蛋白。第一, 從苦瓜種子中純化出一種二型核糖體失活蛋白MCL。體外細胞試驗和體內裸鼠試驗顯示MCL 能夠有效抑制鼻咽癌細胞CNE-l 和CNE-2 生長。第二, 苦瓜種于中一個新的核糖核酸酪RNase MC2被分離出來。RNase MC2 通過調控半胱氨酸依賴性細胞死亡蛋白晦(Caspase)信號途徑和絲裂原活化蛋白激酶(MAPKs) 信號途徑誘導乳腺癌MCF-7 細胞凋亡。第三, 從宮粉羊蹄甲種子中提取一種具有抑制腫瘤細胞生長的蛋白酪抑制劑BvvTI 。第四, 從紅花羊蹄甲種子中提取出一與BvvTI 類似的具有抗腫瘤生長的蛋白酶抑制劑BPLTI。 第五，特長秋紫莢豆中存在一個血液凝集素EAPl。EAPL具有制止HIV-l 逆轉錄酶活性, 抗腫瘤, 誘導一氧化氮生成功效。第六, 從另外一種四季豆, 藍虎王, 中提取出一個血液凝集素BTKL。BTKL 通過誘導肝癌HepG2細胞出現DNA 斷裂, 細胞核破壞, 升高線粒體膜通透性, 誘導一氧化氮和細胞因予的表達, 從而導致其凋亡。 / 總之, 上述實驗結果表明, 這六種蛋白具有一定的藥用前景, 可以作為治療艾滋病和不同腫瘤的候造藥物或者候選輔助藥物。進一步體內實驗和臨床實驗評價其療效值得開展。 / Viral pathogens, environmental carcinogens, and unhealthy diets cause severe damage to humans, leading to the acquirement of different stubborn diseases exemplified by AIDS/HIV and neoplasms. Screening of new drugs from natural products, especially from traditional Chinese medicine, provides a promising strategy for these patients. Proteins with potential medicinal applications include ribosome-inactivating proteins (RIPs), ribonucleases, lectins, protease inhibitors and others. The intent of this research proposal is to isolate and characterize proteins with therapeutic potential from plant seeds. / In this project, six medicinal proteins of different origins have been purified by liquid chromatography. One of them is Momordica charantia lectin (MCL), which is a type 11 RIP from the seeds of bitter gourd (M. charantia, BG), with antitumor activity toward human nasopharyngeal carcinoma cells in vitro and in vivo. We have purified a new ribonuclease, named RNase MC2, from BG seeds. It selectively induces apoptosis in breast cancer cells associated with caspase pathways induction and MAPKs activation. Two Kunitz-type trypsin inhibitors, termed BvvTI and BPLTI, have been purified and characterized from the seeds of Bauhinia variegata var. variegata, and B. purpurea L., respectively. EAPL, a lectin with anti-HIV-l reverse transcriptase, antitumor, and nitric oxide (NO) inducing activities was purified from seeds of Phaseolus vulgaris cv. Extralong autumn purple bean. Finally, BTKL is a new P. vulgaris lectin that induced selective toxicity on human liver carcinoma Hep G2 cells. / In conclusion, the above results evince that these proteins are good candidates for the exploration of anti-HIV and/or antitumor drugs or adjuvants. Further research on their efficacies in in vivo as well as clinical trials is warranted. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Fang, Fei. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 162-187). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / ABSTRACT --- p.ii / 中文摘要 (CHINESE ABSTRACT) --- p.iii / ACKNOWLEDGEMENTS --- p.iv / PUBLICATIONS --- p.v / LIST OF ABBREViATIONS --- p.ix / LIST OF FIGURES --- p.x / LIST OF TABLES --- p.xii / Chapter CHAPTER1 --- GENERAL INTRODUCTION --- p.1 / Chapter 1.1 --- Prelude --- p.2 / Chapter 1.2 --- Literature review of bitter gourd --- p.4 / Chapter 1.2.1 --- Anti-diabetic property of BG --- p.5 / Chapter 1.2.2 --- Anti-HIV activity of BG --- p.15 / Chapter 1.2.3 --- Antitumor activity of BG --- p.18 / Chapter 1.2.4 --- Looking forward --- p.25 / Chapter 1.2.5 --- Conclusions --- p.29 / Chapter 1.3 --- Research rationale, design, and brief results --- p.35 / Chapter CHAPTER2 --- PURIFICATION AND CHARACTERIZATION OF RIBOSOME INACTIVATING PROTEIN --- p.39 / Chapter 2.1 --- Momordica charantia lectin, a type 11 ribosome inactivating protein, exhibits antitumor activity toward human nasopharyngeal carcinoma cells in vitro and in vivo --- p.40 / Chapter 2.1.1 --- Introduction --- p.40 / Chapter 2.1.2 --- Materials and methods --- p.42 / Chapter 2.1.3 --- Results --- p.46 / Chapter 2.1.4 --- Discussion --- p.59 / Chapter CHAPTER 3 --- PURIFICATION AND CHARACTERIZATION OF RIBONUCLEASE --- p.64 / Chapter 3.1 --- RNase MC2: A new Momordica charantia ribonuclease that selectively induces apoptosis in breast cancer cells associated with MAPKs activation and caspase pathways induction --- p.66 / Chapter 3.1.1 --- Introduction --- p.66 / Chapter 3.1.2 --- Materials and methods --- p.67 / Chapter 3.1.3 --- Results --- p.69 / Chapter 3.1.4 --- Discussion --- p.79 / Chapter CHAPTER 4 --- PURIFICATION AND CHARACTERIZATION OF PROTEASE INHIBITORS --- p.84 / Chapter 4.1 --- Bauhinia variegata var variegata trypsin inhibitor: from isolation to potential medicinal applications --- p.86 / Chapter 4.1.1 --- Introduction --- p.86 / Chapter 4.1.2 --- Materials and methods --- p.86 / Chapter 4.1.3 --- Results --- p.89 / Chapter 4.1.4 --- Discussion --- p.97 / Chapter 4.2 --- A potential human hepatocellular carcinoma inhibitor from Bauhinia purpurea L.seeds: From purification to mechanism exploration --- p.99 / Chapter 4.2.1 --- Introduction --- p.99 / Chapter 4.2.2 --- Materials and methods --- p.100 / Chapter 4.2.3 --- Results --- p.101 / Chapter 4.2.4 --- Discussion --- p.112 / Chapter CHAPTER 5 --- PURIFICATION AND CHARACTERIZATION OF MEDICINAL LECTINS --- p.114 / Chapter 5.1 --- A Lectin with Anti-HIV-l Reverse Transcriptase, Antitumor and Nitric Oxide Inducing Activities from Seeds of Phaseolus vulgaris cv Extra-long Autumn Purple Bean --- p.116 / Chapter 5.1.1 --- Introduction --- p.118 / Chapter 5.1.2 --- Materials and methods --- p.119 / Chapter 5.1.3 --- Results --- p.123 / Chapter 5.1.4 --- Discussion --- p.132 / Chapter 5.2 --- A new Phaseolus vulgaris lectin induces selective toxicity on human liver carcinoma Hep G2 cells --- p.136 / Chapter 5.2.1 --- Introduction --- p.136 / Chapter 5.2.2 --- Materials and methods --- p.137 / Chapter 5.2.3 --- Results --- p.138 / Chapter 5.2.4 --- Discussion --- p.150 / Chapter CHAPTER6 --- CONCLUSION AND FUTURE PERSPECTiVES --- p.154 / Chapter 6.1 --- Conclusions --- p.156 / Chapter 6.2 --- Future perspectives --- p.159 / References --- p.162

by Kar-Keung Ching. / "May 2000." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (p. 154-173). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Rad/Rem/Rem2/Gem/Kir (RGK) proteins are Ras-like GTPases with diverse (and expanding) functions including: regulating cytoskeleton dynamics, cell proliferation, synaptogenesis, and inhibition of high voltage-dependent calcium (CaV) channels. Furthermore, they have tissue-specific distribution with Rem and Rad most highly expressed in the heart. Indeed, the importance of Rem and Rad in the cardiovascular system is underscored by a number of studies linking them to disease states including cardiac hypertrophy, cardiac fibrosis, and inflammation. A hallmark feature of RGK proteins is their ability to inhibit current through CaV channels (ICa) and in fact, they are recognized as the most potent endogenous inhibitors of ICa. However, how RGK proteins are regulated and what their physiological role is are unknown. Understanding these points is critical for defining the patho-physiological roles of RGK proteins. My thesis work contributes towards the RGK field on two fronts: First, we demonstrate that RGK proteins are non-canonical G-proteins in the context of their ability to undergo nucleotide regulation and second, we reveal a novel paradigm of RGK-mediated inhibition on CaV channels. In Chapters 2 and 3, we show that Rem and Rad are are non-canonical G-proteins with respect to the regulatory role of their guanine nucleotide binding pocket (GNBP). Canonical Raslike G-proteins contain a conserved G-domain that encompass a GNBP and is important for guanine nucleotide binding and hydrolysis. Since RGK proteins also possess a G-domain and GNBP as well as demonstrate bona fide nucleotide binding, it was initially thought that they were regulated in a manner similar to other Ras proteins. However, subsequent studies suggested that RGK proteins may not obey such a classical model and as a result, the regulatory role of their GNBP in the G-domain was unclear. By using a wide range of functional measurements (CaV1.2 currents, Ca2+ transients, β-subunit binding), we demonstrate that RGK proteins Rem and Rad are non-canonical G-proteins. Utilizing point mutants that abolish GTPbinding and prevent GTPase activity (RemT94N and RadS105N), we show that only some cellular functions are dependent on an operational nucleotide binding pocket while others are unperturbed. Specifically, Rem- and Rad-mediated inhibition of ICa is independent of guanine nucleotide regulation whereas protein interactions with the b-subunit of CaV channels (CaVβ) and protein stability are sensitive to nucleotide regulation. We also discover skeletal and cardiac actin to be novel binding partners of Rem. And lastly, we observe differences between the effects of Rem and Rad on their degree of ICa inhibition in cardiac myocytes. Thus, Rem and Rad are non-canonical G-proteins with respect to the regulatory role of their GNBP. In collaboration with a close colleague, Akil Puckerin, Chapter 4 reveals a novel mechanism behind RGK-mediated inhibition of ICa. Together, we show RGK proteins display different modes of inhibition against specific CaV channels and that we can utilize this property to design calcium channel blockers which inhibit CaV channels in an isoform specific manner. We demonstrate this by designing Rem and Rad mutants which have diminished CaVβ capacity, termed Rem-βNULL and Rad-βNULL, respectively. Characterization of these mutants using wholecell patch clamp experiments revealed that Rem-βNULL inhibits only CaV1.2 whereas Rad-βNULL inhibits only CaV1.2 and CaV2.2. Thus, our results describe the first genetically encoded calcium channel blocker that can selectively distinguish amongst L-type channels. Altogether, this thesis work contributes towards our understanding of RGK protein regulation function and the underlying mechanisms by which they inhibit ICa. These findings advance the field both from a mechanistic and physiological standpoint, and will be of great importance towards investigating the patho-physiological role of RGK proteins.

A 12-kDa ribonuclease was purified from Pleurotus sajor-caju . The ribonuclease inhibited fungi growth and two species of bacteria, Pseudomonas aeruginosa and Staphylococcus aureus. It reduced the viability of hepatoma and leukemia cells and inhibited translation in a cell-free rabbit reticulocyte lysate system. / A 13-kDa lectin was isolated from Collybia veultipes. Its N-terminal sequence shows some similarity to other fungal immunomodulatory proteins. It stimulated [3H-methyl] thymidine uptake by mouse splenocytes and inhibited proliferation of leukemia cells. / A 14.4-kDa antifungal protein was purified from Agrocybe cylindracea . It exerted antifungal activity but lacked inhibitory activity against bacteria when tested up to 300 muM. It attenuated the activity of HIV-1 reverse transcriptase. / A 17-kDa hemolysin was purified from Pleurotus eryngii. It exhibited cytotoxicity toward leukemia cells but not toward fungi. It exhibited antibacterial activity against Bacillus species. / A 27.5-kDa antifungal protein, with an N-terminal sequence similar to heat shock protein and endoglucanase, was purified from Lentinula edodes. It inhibited fungal growth and exerted an inhibitory activity on HIV-1 reverse transcriptase and proliferation of leukemia cells. / A 7-kDa ubiquitin-like protein was purified from Agrocybe cylindracea . It showed antiproliferative activity on leukemia and hepatoma cell lines, and enhanced nitric oxide production in murine peritoneal macrophages. / An 18-kDa lectin, with an N-terminal sequence similar to some lectins and fungal immunomodulatory proteins, was isolated from Ganoderma capense. It exhibited potent mitogenic activity toward mouse splenocytes, and antiproliferative activity toward leukemia and hepatoma cells. / Mushrooms produce a variety of proteins with interesting biological activities. They include lectins, antifungal proteins, ribonucleases, ubiquitin-like proteins, hemolysins and other peptides. / This study demonstrates that different types of defense proteins with diverse biological activities are produced by mushrooms. Some overlap is observed in the spectra of biological activities of the same type of defense proteins. The results of protein characterization provide crucial information for future genetic manipulation in agricultural and food industries. Studies of the in vitro action of the abovementioned defense proteins on fungi, bacteria, viral enzyme, immune cells and cancer cells indicate that the proteins are potentially exploitable drug agents. / Ngai Hung-kui. / "July 2005." / Adviser: Ng Tzi Bun. / Source: Dissertation Abstracts International, Volume: 67-01, Section: B, page: 0012. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 228-294). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Abstract not available

Bibliography: leaves 182-198. Improvements in the current production system of inclusion bodies and the downstream processing sequence are essential to maintain a competitive advantage in the market place. Optimisation of fermentation is considered to improve production yield; then flotation as a possible inclusion body recovery method.

Detection of biomolecules is important for the diagnosis and treatment of diseases. Low concentration detection, specific biomolecule detection, and point-of-care use are appealing characteristics for biosensors because of the possibility of early detection and quick results of specific biomolecules. Furthermore, inexpensive biosensors are appealing so that they are accessible to the general population. The biosensors in this study have the potential to satisfy these characteristics. In this study graphene field-effect transistors (G-FET) were fabricated. Graphene was grown using chemical vapor deposition (CVD) and transferred to a silicon/silicon oxide substrate. The CVD method is the most scalable and cost-effective method of producing graphene for devices. Standard photolithography was used to pattern and then deposit metal electrodes. Two separate experiments were conducted; one using electrostatic attraction to bind protein to the active area of the G-FET to detect the protein poly-L-lysine (PLL) and one using an aptamer modified G-FET to selectively detect the protein thrombin. Analyte was delivered using a homebuilt, pressure driven, microfluidic, mass flow system. Both experiments showed a detection of the protein. The PLL experiment showed a clear change in the effective gate voltage of the G-FET. The thrombin experiment showed a change in the effective gate voltage that varied with differing concentrations of thrombin present. Furthermore, in the thrombin experiment by changing from a thrombin solution back to buffer the effective gate voltage was brought back to its original value. A competing protein was introduced and gave a signal comparable to the signal of a 10 times smaller concentration of thrombin. All of this shows that CVD grown graphene in a FET biosensor can be used for protein detection. Furthermore, the specific detection of thrombin suggests that aptamer modified G-FETs with CVD grown graphene can be used as a protein specific biosensor. / Graduation date: 2013

Recombinant human macrophage colony stimulating factor beta (rhm-CSFβ) is a glycoprotein that stimulates the proliferation, differentiation and survival of cells belonging to the monocyte-macrophage lineage. It contains nine inter-subunit and intra-subunit disulfide bonds and represents an excellent model system for studying disulfide bond formation during protein folding because the assembly of its monomeric subunits and the maturation of its biological activity depend on the progressive formation of the correct disulfide structure during in vitro folding. Knowledge obtained from these studies can be potentially useful in understanding the roles of disulfide bond formation during protein folding in general. rhm-CSF8 was modified by partial reduction of disulfide bonds, yielding CN¹⁵⁷'¹⁵⁹-modified rhm-CSFβ. The modification did not affect the biological activity, stability, or the overall conformation of the protein. However, the C-terminal regions near the modification sites were shown to exhibit faster deuterium exchange behavior as a result of the chemical modification, indicating that the C-terminal regions became more flexible. Folding kinetics of rhm-CSFβ and CN¹⁵⁷'¹⁵⁹-modified rhm-CSFβ were shown to be essentially the same, suggesting that the modification did not affect the folding kinetics of the oxidized rhm-CSFβ. The denatured and reduced rhm-CSFβ was refolded with the aid of a chemical oxidant. The data indicated that the in vitro folding rhm-CSFβ proceeded via multiple pathways involving monomeric and dimeric intermediates. Disulfide bond shuffling catalyzed by GSH/GSSG represented an important isomerization step in folding. A dimeric intermediate, D-SS8-cam2, was isolated and identified as a kinetic trap, perhaps requiring significant structural arrangement to convert to the native protein. The heterogeneous folding mixture detected by both disulfide bond quenching and H/D pulsed labeling indicate that rhm -CSFβ folding is a diffusion like process as described by the folding funnel model. / Graduation date: 2003