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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Development of an immunoassay for tartrate-resistant acid phosphatase and its use in the monitoring of bone metabolism.

January 1993 (has links)
Chi Keung Cheung. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 219-251). / Chapter CHAPTER I --- LITERATURE REVIEW / Chapter 1 --- The structure of bone --- p.2 / Chapter 1.1. --- The cortical bone --- p.3 / Chapter 1.2. --- The cancellous bone --- p.3 / Chapter 2 --- The composition of bone --- p.3 / Chapter 2.1. --- Bone minerals --- p.4 / Chapter 2.2. --- The organic matrix --- p.4 / Chapter 2.3. --- The bone cells --- p.9 / Chapter 2.3.1. --- The osteoblast and the osteocyte --- p.9 / Chapter 2.3.2. --- The osteoclast --- p.11 / Chapter 3 --- Bone turnover - modelling and remodelling of bone --- p.13 / Chapter 3.1. --- Postulated sequence of bone remodelling --- p.14 / Chapter 4 --- Regulation of bone resorption --- p.16 / Chapter 4.1. --- Role of osteoblast and the lining cell on bone resorption --- p.17 / Chapter 5 --- Regulation of bone formation --- p.19 / Chapter 6 --- Effects of systemic hormones and local factors on bone metabolism --- p.20 / Chapter 6.1. --- Parathyroid hormone --- p.20 / Chapter 6.2. --- "1,25-dihydroxyvitamin D3" --- p.22 / Chapter 6.3. --- Calcitonin --- p.23 / Chapter 6.4. --- Prostaglandins --- p.23 / Chapter 6.5. --- Sex hormones --- p.24 / Chapter 6.6. --- Glucocorticoid --- p.26 / Chapter 6.7. --- Growth hormone --- p.27 / Chapter 6.8. --- Insulin --- p.28 / Chapter 6.9. --- Thyroid hormones --- p.29 / Chapter 6.10. --- Other systemic and local factors --- p.30 / Chapter 7 --- Indices of bone turnover --- p.34 / Chapter 8 --- Non-biochemical indices of bone metabolism --- p.34 / Chapter 8.1. --- Radionuclide bone scan --- p.34 / Chapter 8.2. --- Radiokinetic assessment --- p.35 / Chapter 8.3. --- Bone biopsy --- p.35 / Chapter 8.4. --- Bone densitometry --- p.36 / Chapter 9 --- Biochemical indices of bone metabolism --- p.37 / Chapter 10 --- Biochemical markers of bone formation --- p.38 / Chapter 10.1. --- Alkaline phosphatase --- p.38 / Chapter 10.1.1. --- Role and origin of bone alkaline phosphatase isoenzyme --- p.39 / Chapter 10.1.2. --- Measurement of bone alkaline phosphatase --- p.41 / Chapter 10.1.2.1. --- Heat inactivation --- p.42 / Chapter 10.1.2.2. --- Chemical inactivation --- p.43 / Chapter 10.1.2.3. --- Immunological methods --- p.44 / Chapter 10.1.2.4. --- High performance liquid chromatography --- p.45 / Chapter 10.1.2.5. --- Gel electrophoresis --- p.45 / Chapter 10.1.2.6. --- Isoelectric focusing --- p.47 / Chapter 10.2. --- Osteocalcin --- p.48 / Chapter 10.3. --- Osteonectin --- p.51 / Chapter 10.4. --- Matrix Gla-protein --- p.51 / Chapter 10.5. --- Other non-collagenous proteins --- p.52 / Chapter 10.6. --- Urinary Gla concentration --- p.52 / Chapter 10.7. --- Collagen peptides and extension peptides --- p.54 / Chapter 11 --- Biochemical markers of bone resorption --- p.55 / Chapter 11.1. --- Urine hydroxyproline --- p.55 / Chapter 11.2. --- Pyridinium cross-links --- p.58 / Chapter 11.3. --- Acid phosphatase --- p.60 / Chapter 11.3.1. --- Acid phosphatase isoenzymes --- p.60 / Chapter 11.3.2. --- The band 5 acid phosphatase isoenzyme genetics and characteristics --- p.62 / Chapter 11.3.3. --- Band 5 acid phosphatase as marker of osteoclastic function --- p.64 / Chapter 11.3.4. --- Measurement of osteoclastic acid phosphatase --- p.67 / Chapter 11.3.4.1. --- Specific chemical inhibitor --- p.67 / Chapter 11.3.4.2. --- Electrophoresis --- p.67 / Chapter 11.3.4.3. --- Immunological methods --- p.68 / Chapter 12 --- Problems with current biochemical markers of bone metabolism --- p.68 / Chapter 13 --- Aims of this study --- p.70 / Chapter CHAPTER II --- PURIFICATION OF TARTRATE-RESISTANT ACID PHOSPHATASE AND THE DEVELOPMENT OF AN IMMUNOASSAY FOR IT'S MEASUREMENT / Chapter 1 --- Introduction --- p.72 / Chapter 2 --- Materials and methods --- p.75 / Chapter 2.1. --- Chemicals and reagents --- p.75 / Chapter 2.1.1. --- Apparatus --- p.76 / Chapter 2.2. --- Methods --- p.77 / Chapter 2.2.1. --- Cord serum --- p.77 / Chapter 2.2.2. --- Measurement of tartrate-resistant acid phosphatase activity --- p.77 / Chapter 2.2.3. --- Measurement of protein concentration --- p.80 / Chapter 2.2.4. --- Purification of TRACP from cord plasma --- p.82 / Chapter 2.2.4.1. --- Cation-exchange column chromatography --- p.83 / Chapter 2.2.4.2. --- Gel filtration column chromatography --- p.84 / Chapter 2.2.4.3. --- Concanavalin A-affinity column chromatography --- p.85 / Chapter 2.2.4.4. --- Preparative isoelectric focusing (IEF) --- p.86 / Chapter 2.3. --- Characterisation of purified TRACP --- p.90 / Chapter 2.3.1. --- Polyacrylamide gel electrophoresis (PAGE) --- p.91 / Chapter 2.3.2. --- "Optimum pH, substrate specificity and the effects of potential activators and inhibitors on TRACP activity" --- p.99 / Chapter 2.3.3. --- Amino acid composition of purified TRACP --- p.101 / Chapter 2.4. --- Methods for raising anti-human TRACP antibody and characterisation of the antiserum --- p.102 / Chapter 2.4.1. --- Production of rabbit anti-human TRACP antibody --- p.102 / Chapter 2.4.2. --- Determination of the titre of rabbit anti-human TRACP antibody --- p.103 / Chapter 2.4.3. --- Immunoblotting analyses for cross reactivity study --- p.103 / Chapter 2.4.4. --- Immunohistochemical study for antibody specificity --- p.105 / Chapter 2.4.5. --- Cross reactivity study of the rabbit anti-human TRACP antibody to some tissue preparations --- p.107 / Chapter 2.5. --- Enzyme linked immunosorbent assay for TRACP --- p.109 / Chapter 2.5.1. --- Optimisation and evaluation of the new ELISA method for TRACP --- p.111 / Chapter 3 --- RESULTS --- p.113 / Chapter 3.1. --- "Precision of methods for the determination of protein, TRACP and phosphate." --- p.113 / Chapter 3.2. --- Isolation and purification of TRACP --- p.113 / Chapter 3.2.1. --- Concanavalin A affinity chromatography --- p.120 / Chapter 3.2.2. --- Isoelectric focusing (IEF) --- p.120 / Chapter 3.3. --- Characterisation and homogeneity of purified TRACP --- p.128 / Chapter 3.3.1. --- Characterisation of purified TRACP --- p.128 / Chapter 3.3.2. --- Homogeneity of purified TRACP --- p.132 / Chapter 3.3.3. --- Amino acid composition --- p.136 / Chapter 3.4. --- Characterisation of the rabbit anti-human TRACP antibody --- p.136 / Chapter 3.4.1. --- Antibody specificity - immunoblotting study --- p.139 / Chapter 3.4.2. --- Antibody specificity - cross reactivity with partially purified non-cord plasma TRACP --- p.142 / Chapter 3.4.3. --- Antibody specificity - immunohistochemical study --- p.145 / Chapter 3.5. --- Enzyme linked immunosorbent assay for TRACP --- p.145 / Chapter 3.5.1. --- Optimal concentration of antigen for coating of microtitre plate --- p.145 / Chapter 3.5.2. --- Kinetics of reaction with the primary rabbit anti-human TRACP antibody --- p.149 / Chapter 3.5.3. --- "Precision, recovery and assay range" --- p.149 / Chapter 4 --- DISCUSSION --- p.155 / Chapter 4.1. --- Purification of cord plasma TRACP --- p.155 / Chapter 4.2. --- Characterisation of cord plasma TRACP --- p.158 / Chapter 4.3. --- Characterisation of rabbit anti-human TRACP antibody --- p.163 / Chapter 4.4. --- Enzyme immunoassay for TRACP --- p.165 / Chapter CHAPTER III --- STUDY OF SERUM TRACP IN HEALTHY SUBJECTS AND IN PATIENTS WITH BONE RELATED DISEASES / Chapter 1 --- Introduction --- p.168 / Chapter 2 --- Materials and methods --- p.171 / Chapter 2.1. --- Subjects --- p.171 / Chapter 2.1.1. --- Healthy subjects --- p.171 / Chapter 2.1.2. --- Patients --- p.172 / Chapter 2.1.2.1. --- Post-menopausal women on hormone replacement therapy --- p.172 / Chapter 2.1.2.2. --- Hip fracture patients --- p.173 / Chapter 2.1.2.3. --- Other patients --- p.174 / Chapter 2.3. --- Measurement of other biochemical parameters --- p.175 / Chapter 2.3.1. --- Bone alkaline phosphatase --- p.175 / Chapter 2.3.2. --- "Measurement of urine hydroxyproline, creatinine, calcium, osteocalcin, thyroid hormones and parathyroid hormone" --- p.176 / Chapter 2.4. --- Statistics --- p.178 / Chapter 3 --- RESULTS --- p.179 / Chapter 3.1. --- Healthy subjects --- p.179 / Chapter 3.2. --- Serum TRACP concentration in post-menopausal women before and after hormone replacement therapy --- p.185 / Chapter 3.3. --- TRACP concentration in elderly subjects with hip fractures --- p.189 / Chapter 3.4. --- Serum TRACP concentrations in patients with other bone related diseases --- p.190 / Chapter 3.4.1. --- Hyperthyroidism --- p.194 / Chapter 3.4.2. --- Hyperparathyroidism --- p.198 / Chapter 3.4.3. --- Haemodialysis --- p.201 / Chapter 4 --- DISCUSSION --- p.204 / GENERAL DISCUSSION --- p.216 / REFERENCES --- p.219
32

Cloning and analysis of promoter regulating the expression of a purple acid phosphatase.

January 2001 (has links)
Zhang Siyi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 97-109). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.iii / List of Tables --- p.vii / List of Figures --- p.viii / List of Abbreviations --- p.x / Chapter Chapter 1: --- General Introduction --- p.1 / Chapter Chapter 2: --- Literature Review --- p.3 / Chapter 2.1 --- Phosphorus and higher plants --- p.3 / Chapter 2.1.1 --- Phosphorus is a macronutrient in higher plants --- p.3 / Chapter 2.1.2 --- The forms of phosphorus in plant cells --- p.3 / Chapter 2.1.3 --- Phosphorus compartments and pools in plant cells --- p.6 / Chapter 2.2 --- The acquisition of phosphorus in higher plants --- p.8 / Chapter 2.2.1 --- The forms of phosphorus absorbed by higher plants --- p.8 / Chapter 2.2.2 --- Soil phosphorus bioavailability --- p.9 / Chapter 2.2.3 --- Uptake and transportation of phosphorus --- p.10 / Chapter 2.3 --- Adaptive responses of higher plants to phosphorus deficiency --- p.11 / Chapter 2.3.1 --- Phosphorus homeostasis --- p.12 / Chapter 2.3.2 --- Enhancement of phosphorus uptake --- p.14 / Chapter 2.3.3 --- Phosphorus scavenging and recycling --- p.16 / Chapter 2.4 --- Regulation of gene expression under phosphorus starvation --- p.18 / Chapter 2.5 --- Acid phosphatase and purple acid phosphatase in plants --- p.22 / Chapter 2.5.1 --- Acid phosphatases --- p.22 / Chapter 2.5.2 --- Purple acid phosphatase (PAP) --- p.26 / Chapter Chapter 3: --- Hypothesis --- p.31 / Chapter Chapter 4: --- Materials and Methods --- p.33 / Chapter 4.1 --- Materials --- p.33 / Chapter 4.1.1 --- Chemicals --- p.33 / Chapter 4.1.2 --- Plant materials --- p.33 / Chapter 4.1.3 --- Plasmid vectors and bacterial strains --- p.33 / Chapter 4.1.4 --- DNA sequencing --- p.34 / Chapter 4.1.5 --- Softwares: --- p.34 / Chapter 4.2 --- Methods: --- p.35 / Chapter 4.2.1 --- Survey of PAP occurrence in higher plants --- p.35 / Chapter 4.2.2 --- Determination of multi-gene family and gene copy number of PAPin tomato genome --- p.40 / Chapter 4.2.3 --- Effect of environmental Pi on the morphology of tomato and APase induction --- p.43 / Chapter 4.2.4 --- PAP expression in tomato seedlings growing at different Pi concentrations --- p.46 / Chapter 4.2.5 --- Genomic library construction and PAP promoter isolation --- p.48 / Chapter 4.2.6 --- PAP promoter activity assay by transient expression of reporter gene..… --- p.52 / Chapter Chapter 5: --- Results --- p.56 / Chapter 5.1 --- Identification of PAP gene in higher plants --- p.56 / Chapter 5.1.1 --- Design of primers and total RNA extraction --- p.56 / Chapter 5.1.2 --- RT-PCR --- p.57 / Chapter 5.1.3 --- Further investigation of PAP homologous sequences in monocotyledons --- p.60 / Chapter 5.2 --- Determination of multi-gene family and gene copy number of tomato PAP gene (TPAP 1) --- p.62 / Chapter 5.2.1 --- Determination of TPAP 1 copy number --- p.62 / Chapter 5.2.2 --- Determination of tomato PAP multi-gene family --- p.63 / Chapter 5.3 --- Effect of environmental phosphorus on the morphology of tomato seedling and APase induction --- p.66 / Chapter 5.3.1 --- Morphological changes of tomato seedlings under phosphorus starvation --- p.66 / Chapter 5.3.2 --- Acid phosphatase assays --- p.72 / Chapter 5.4 --- The phosphorus-regulated expression of tomato PAP --- Northern blot analysis --- p.74 / Chapter 5.5 --- Genomic library construction and PAP promoter isolation --- p.76 / Chapter 5.6 --- PAP promoter sequence --- p.79 / Chapter 5.7 --- Promoter activity assay through transient expression of reporter gene --- p.84 / Chapter 5.7.1 --- Effect of untranslation region of PAP gene --- p.84 / Chapter 5.7.2 --- Assay of PAP promoter activities regulated by phosphorus --- p.85 / Chapter Chapter 6: --- Discussion --- p.88 / Chapter 6.1 --- The wide occurrence and high conservation of plant PAP --- p.88 / Chapter 6.2 --- Tomato as a model plant and the organization of PAP gene in genome --- p.89 / Chapter 6.3 --- Morphological changes of tomato under phosphorus starvation and the induction of APase --- p.90 / Chapter 6.4 --- Regulation of PAP in tomato --- p.92 / Chapter 6.5 --- Isolation of PAP promoter --- p.92 / Chapter 6.6 --- Assay of PAP promoter activity --- p.93 / Chapter 6.7 --- Future perspectives --- p.94 / Chapter Chapter 7: --- Conclusion --- p.95 / References --- p.97
33

Promoter analysis and expression of the tomato purple acid phosphatase (TPAP1) in tobacco.

January 2004 (has links)
Suen Pui Kit. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 154-168). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.iii / List of Figures --- p.vii / List of Tables --- p.ix / List of Abbreviations --- p.x / Chapter Chapter 1: --- Introduction --- p.1 / Chapter Chapter 2: --- Literature Review --- p.3 / Chapter 2.1 --- Phosphorus and Plants --- p.3 / Chapter 2.1.1 --- Importance of phosphorus --- p.3 / Chapter 2.1.2 --- Phosphorus is a limiting nutrient --- p.3 / Chapter 2.2 --- Responses of Plants to Phosphate Deficiency --- p.4 / Chapter 2.2.1 --- Morphological changes of plants during phosphate deficiency --- p.5 / Chapter 2.2.1.1 --- Modification of the root system --- p.5 / Chapter 2.2.1.2 --- Symbiotic association of roots with mycorrhiza --- p.6 / Chapter 2.2.2 --- Maintenance of phosphate levels in plants during phosphate deficiency --- p.7 / Chapter 2.2.2.1 --- Phosphate homeostasis in plants --- p.7 / Chapter 2.2.2.2 --- "Enhancement of Pi scavenging, recycling and uptake" --- p.9 / Chapter 2.2.2.3 --- Pi-limited metabolism --- p.11 / Chapter 2.2.3 --- Hormones and phosphate starvation responses --- p.12 / Chapter 2.2.4 --- Regulation of gene expression during phosphate starvation --- p.14 / Chapter 2.2.4.1 --- The pho regulon in bacteria and yeast --- p.14 / Chapter 2.2.4.2 --- The coordination of phosphate starvation induced genes in plants --- p.19 / Chapter 2.2.4.3 --- Signaling phosphate starvation --- p.19 / Chapter 2.2.4.4 --- Phosphite and phosphate starvation --- p.21 / Chapter 2.2.4.5 --- Transcriptional regulation during phosphate starvation --- p.22 / Chapter 2.3 --- Acid Phosphatases in Higher Plants --- p.26 / Chapter 2.3.1 --- Enzymatic properties of acid phosphatases --- p.26 / Chapter 2.3.2 --- Localization and function of acid phosphatases --- p.27 / Chapter 2.3.3 --- Expression of acid phosphatases --- p.28 / Chapter 2.4 --- Purple Acid Phosphatases --- p.29 / Chapter 2.4.1 --- Properties of purple acid phosphatases --- p.29 / Chapter 2.4.2 --- Regulation and expression of plant purple acid phosphatase --- p.32 / Chapter 2.5 --- Tomato Purple Acid Phosphatases --- p.33 / Chapter 2.6 --- Promoter Analysis --- p.35 / Chapter 2.6.1 --- Structure of an eukaryotic promoter --- p.35 / Chapter 2.6.2 --- Promoter analysis by deletion mapping --- p.37 / Chapter 2.6.3 --- The computational approaches in promoter analysis --- p.38 / Chapter 2.6.4 --- Transient expression assay and transgenic expression assay --- p.39 / Chapter 2.7 --- Transcriptional Regulation of Tomato Purple Acid Phosphatase Expression --- p.40 / Chapter 2.8 --- Hypothesis --- p.41 / Chapter Chapter 3: --- Materials and Methods --- p.43 / Chapter 3.1 --- Introduction --- p.43 / Chapter 3.2 --- Materials --- p.44 / Chapter 3.2.1 --- Chemicals --- p.44 / Chapter 3.2.2 --- Plant materials --- p.44 / Chapter 3.2.3 --- Plasmid vectors and bacterial strains --- p.44 / Chapter 3.2.4 --- Primers design --- p.45 / Chapter 3.2.5 --- Confirmation of sequence fidelity --- p.46 / Chapter 3.3 --- Cloning of the TPAP1 Promoter Fragments --- p.46 / Chapter 3.3.1 --- Genomic DNA extraction --- p.46 / Chapter 3.3.1.1 --- Materials --- p.46 / Chapter 3.3.1.2 --- Procedures --- p.47 / Chapter 3.3.2 --- Cloning strategy of TPAP1 promoter --- p.47 / Chapter 3.3.3 --- TPAP1 promoter cloning --- p.48 / Chapter 3.3.3.1 --- Long-distance PCR --- p.48 / Chapter 3.3.4 --- Chimeric gene constructs --- p.48 / Chapter 3.3.4.1 --- Chimeric gene construction for particle bombardment --- p.51 / Chapter 3.3.4.2 --- Chimeric gene construction for tobacco transformation --- p.51 / Chapter 3.4 --- Transient Expression Assay of the TPAP1 Promoter Fragments --- p.54 / Chapter 3.4.1 --- TPAP1 promoter activity assay --- p.54 / Chapter 3.4.2 --- Preparation of MS culture medium --- p.54 / Chapter 3.4.3 --- Growing tomato seedlings in MS liquid medium --- p.56 / Chapter 3.4.4 --- Biolistic bombardment --- p.56 / Chapter 3.4.5 --- GUS histochemcial staining --- p.57 / Chapter 3.4.5.1 --- Materials --- p.57 / Chapter 3.4.5.2 --- Procedures --- p.57 / Chapter 3.5 --- Transgenic Assay of the TPAP1 Promoter Fragments --- p.58 / Chapter 3.5.1 --- Materials for tobacco transformation --- p.58 / Chapter 3.5.2 --- Agrobacterium tumefaciens preparation --- p.58 / Chapter 3.5.3 --- Tobacco transformation and regeneration --- p.59 / Chapter 3.5.4 --- Promoter activity analysis --- p.60 / Chapter 3.5.4.1 --- Materials --- p.60 / Chapter 3.5.4.2 --- Procedures --- p.60 / Chapter 3.5.5 --- Southern blot analysis --- p.61 / Chapter 3.5.6 --- RNA isolation --- p.61 / Chapter 3.5.6.1 --- Materials --- p.61 / Chapter 3.5.6.2 --- Procedures --- p.61 / Chapter 3.5.7 --- Northern blot analysis --- p.62 / Chapter 3.6 --- Biochemical Analysis of Acid Phosphatase Activities --- p.63 / Chapter 3.6.1 --- Excretion of acid phosphatase into the environment --- p.63 / Chapter 3.6.2 --- Growing tomato seedlings in MS medium --- p.63 / Chapter 3.6.3 --- Acid phosphatase activity assay by p-nitrophenyl phosphate --- p.64 / Chapter 3.6.4 --- Activity-gel detection --- p.65 / Chapter 3.6.4.1 --- Materials --- p.65 / Chapter 3.6.4.2 --- Procedures --- p.65 / Chapter 3.7 --- "Sequence Analysis of the TPAP1 gene, cDNA and promoter" --- p.66 / Chapter 3.7.1 --- Isolation of TPAPl cDNA --- p.66 / Chapter 3.7.1.1 --- Rapid amplification of cDNA ends (RACE) --- p.66 / Chapter 3.7.1.2 --- RT-PCR --- p.67 / Chapter 3.7.2 --- Isolation of TPAP1 gene --- p.67 / Chapter 3.7.2.1 --- PCR amplification of the TPAP1 gene --- p.67 / Chapter 3.7.2.2 --- TPAP1 gene sequence determination --- p.68 / Chapter 3.7.3 --- Sequence analysis --- p.69 / Chapter 3.8 --- Statistical analysis --- p.70 / Chapter Chapter 4: --- Results --- p.72 / Chapter 4.1 --- "Cloning of the TPAP1 Promoter Fragments, Gene and cDNA" --- p.72 / Chapter 4.1.1 --- TPAP1 promoter fragment constructs --- p.72 / Chapter 4.1.2 --- TPAP1 cDNA cloning --- p.72 / Chapter 4.1.3 --- TPAP1 gene cloning --- p.72 / Chapter 4.2 --- "Sequence analysis of the TPAP1 promoter, gene, cDNA and predicted amino acid sequence" --- p.76 / Chapter 4.2.1 --- "The DNA sequence of the TPAP1 promoter, gene and cDNA" --- p.76 / Chapter 4.2.2 --- Properties of TPAP1 cDNA and protein --- p.83 / Chapter 4.2.3 --- Identification of potential metal ligating residues on TPAP1 --- p.85 / Chapter 4.2.4 --- Phylogenetic relationship of TPAPl to other plant PAPs --- p.86 / Chapter 4.2.5 --- Sequence comparison of 5'UTR ofTPAPl and NtPAP12 --- p.89 / Chapter 4.3 --- APase Activity Assay --- p.90 / Chapter 4.3.1 --- p-NPP APase activity assay --- p.90 / Chapter 4.3.2 --- Activity-gel detection --- p.90 / Chapter 4.4 --- "Comparison of TPAP 1, IAP,SAP 1 and SAP2" --- p.96 / Chapter 4.5 --- Potential Cis-acting Regulatory Elements (CAREs) on the TPAP1 Promoter --- p.100 / Chapter 4.5.1 --- Search for potential CAREs --- p.100 / Chapter 4.5.2 --- Functions of CAREs --- p.100 / Chapter 4.6 --- Transient Expression Analysis --- p.102 / Chapter 4.6.1 --- Biolistic bombardment of TPAP1 promoter fragments into tomato roots --- p.102 / Chapter 4.7 --- Transgenic Expression Analysis --- p.104 / Chapter 4.7.1 --- Transformation of tobacco --- p.104 / Chapter 4.7.2 --- Northern and RT-PCR analysis of GUS expression --- p.110 / Chapter 4.7.3 --- GUS activity analysis --- p.114 / Chapter 4.7.4 --- Histochemical staining of GUS --- p.123 / Chapter Chapter 5: --- Discussions --- p.135 / Chapter 5.1 --- Properties ofTPAPl --- p.135 / Chapter 5.1.1 --- "Structure of the TPAP1 promoter, gene and cDNA" --- p.135 / Chapter 5.1.2 --- Potential flmction(s) ofTPAPl --- p.135 / Chapter 5.1.3 --- The potential relationship between TPAP1 and NtPAP12 --- p.137 / Chapter 5.2 --- Induction of Secretory APases during Pi Starvation --- p.137 / Chapter 5.3 --- Putative Protein Encode by theTPAP 1 cDNA --- p.138 / Chapter 5.4 --- Promoter Analysis of TPAP1 --- p.140 / Chapter 5.4.1 --- Construct preparation --- p.140 / Chapter 5.4.2 --- Potential CAREs located on the TPAP1 promoter --- p.141 / Chapter 5.4.3 --- Transient expression analysis --- p.142 / Chapter 5.4.4 --- Transgenic expression analysis --- p.143 / Chapter 5.4.4.1 --- Northern analysis and RT-PCR analysis of GUS expression --- p.143 / Chapter 5.4.4.2 --- GUS activity analysis --- p.143 / Chapter 5.4.4.3 --- Histochemical staining of GUS --- p.145 / Chapter 5.5 --- Hypothetical Model for TPAP1 Promoter Activities --- p.146 / Chapter 5.5.1 --- Model for expression level --- p.146 / Chapter 5.5.2 --- Models for spatial expressions --- p.148 / Chapter 5.6 --- Future Perspectives --- p.150 / Chapter Chapter 6: --- Conclusions --- p.152 / References --- p.154
34

Produção e caracterização de proteínas quiméricas contendo fosfatases e módulo de ligação à celulose / Production and characterization of a chimeric protein containing phosphatase and cellulose binding module

Gonçalves, Larissa Martins 20 December 2011 (has links)
Introdução e Objetivos. Fosfatases são enzimas promissoras para aplicação na degradação de organofosforados. Por exemplo, a enzima paraoxonase 1 (PON1), associada à lipoproteína de alta densidade (HDL), hidrolisa lactonas, ésteres aromáticos e compostos organofosforados (OP) neurotóxicos. \"Módulos de ligação a carboidrato\" (CBM) têm diversas aplicações biotecnológicas. Nosso objetivo é a obtenção de proteínas quiméricas contendo fosfatases ligadas a um módulo de ligação de celulose, o que possibilitaria a imobilização dessas enzimas em suportes de celulose. Resultados. Como prova de conceito, uma proteína quimérica contendo uma \"fosfatase ácida\" (appA) de E.coli e CBM familia 2 (CBM2) de uma celulase de Xanthomonas axonopodis pv citri foi montada e produzida em E. coli como uma proteína recombinante solúvel. appA-CBM2 purificada demonstrou ser totalmente funcional exibindo atividade de ligação à celulose microcristalina (Avicel PH101) e atividade de fosfatase sobre p-nitrofenil fosfato. A ligação à Avicel evidenciou um comportamento de saturação descrito por uma \"constante de ligação\" (Kb) de 26 mg e um \"máximo de ligação\" (Bmax) de 4,45 U/µg. Além disso, a ligação de appA-CBM2 em Avicel foi maior em pH 2,5 e diminuiu acima de pH 6,5, como observado anteriormente para CBM2. Finalmente, o efeito de concentração de p-nitrofenil fosfato na atividade catalítica de appA-CBM2 e appA foi idêntico, exibindo um Km de 2,8 mM. Portanto, esses dados mostram que o conceito de uma proteína que combina as propriedades da fosfatase e do domínio de ligação à celulose é possível e funcional. De forma similar, os segmentos de DNA que codificam para o CBM2 e para a PON1 de Homo sapiens, foram fusionados resultando em um segmento que codifica para uma proteína quimérica (PON1-CBM2). PON1 nativa e PON1-CBM2 foram produzidas na forma solúvel e ativa em E.coli cepa Arctic. Embora não tenha sido viável sua purificação, estas enzimas foram caracterizadas. PON1-CBM2 liga-se em Avicel PH101 com um comportamento de saturação, descrito por uma constante de ligação (Kb) de 27 mg, valor idêntico àquele observado para appA-CBM2, o que sugere que o domínio CBM2 é igualmente funcional nestas duas enzimas quiméricas. PON1-CBM2 também exibe atividade paraoxonásica com Km similar àquele observado para PON1 nativa (1,3 mM), sugerindo que o \"domínio\" PON1 encontra-se totalmente funcional na enzima quimérica. Conclusão. Uma estratégia para a construção e expressão heteróloga em E. coli de PON1 e das enzimas quiméricas appA-CBM2 e PON1-CBM2 foi desenvolvida. As enzimas quiméricas mostraram-se totalmente funcionais e conservaram as propriedades de seus \"domínios\" constituintes. / Introduction and Aims. Phosphatases are promising enzymes for application in the degradation of organophosphates, whereas carbohydrate binding module has significant and demonstrated biotechnological applications. The high-density lipoprotein-associated enzyme paraoxonase 1 (PON1) hydrolyzes lactones, aromatic esters, and neurotoxic organophosphorus (OP) compounds. Our aim is to obtain chimeric proteins containing a phosphatase domain linked to a carbohydrate binding module (CBM), which could be immobilized on a cellulose supports. Results. As a proof of concept, a chimeric protein combining an acid phosphatase (appA) from E.coli and a CBM family 2 (CBM2) from Xanthomonas axonopodis pv. citri was assembled and produced in E.coli as a recombinant soluble protein. Purified appA-CBM2 was fully functional, was bound to microcrystalline cellulose and exhibited phosphatase activity upon p-nitrophenyl phosphate. The binding to microcrystalline cellulose Avicel PH101 exhibited saturation with a binding constant (Kb) of 26 and a maximum binding (Bmax) of 4,45 U/µg. In addition, the binding was higher at pH 2.5 and decreased above pH 6.5, as previously observed for CBM2. Finally, effect of p-nitrophenyl phosphate concentration on appA-CBM2 and native appA activities were identical, exhibiting a Km of 2.8 mM. Taken together, these data show that the conceptual design of a protein combining the properties and biotechnological advantages of phosphatases and cellulose binding domains is possible and functional. Similarly, DNA segments coding for CBM2 and for PON1 from Homo sapiens combined resulting in a segment coding for a chimeric protein (PON1-CBM2). Native PON1 and PON1-CBM2 were produced as recombinant protein in E. coli Arctic. Although purification was not accomplished, these enzymes were characterized. PON1-CBM2 binds to microcrystalline cellulose, exhibiting a saturation behavior described by a Kb of 27 mg. PON1 and PON1- CBM2 have the same Km for paraoxon (1.3 mM), indicating that the phosphatase domain was fully functional. Conclusion. An effective strategy for heterologous expression of the native PON1 and chimeric appA-CBM2 and PON1-CBM2 in E. coli was attained. The chimeric enzymes were fully functional and maintained the properties of their original domains
35

Indução da expressão in vivo e caracterização cinética da fosfatase ácida de Enterobacter sp. isolada de raízes de orquidáceas /

Sato, Vanessa Sayuri. January 2011 (has links)
Resumo: A capacidade de bactérias endofíticas em solubilizar fosfato inorgânico é alvo de grande interesse por parte dos microbiologistas, uma vez que as fosfatases são responsáveis por hidrolisar compostos orgânicos produzindo fósforo solúvel. Dessa forma, a fosfatase ácida ligada à membrana (MBAP) foi obtida a partir de Enterobacter sp. isolada de raízes de Cattleya walkeriana (Orchidaceae) e identificada pelo seqüenciamento do gene 16S rRNA. A expressão da enzima mostrou-se estritamente regulada pelo fósforo (expressão ideal em 7 mm). O pH ótimo aparente (3,5) não foi afetado pela concentração de p-nitrofenilfosfato. Em pH 3,5, a enzima é uma fosfomonidrolase inespecífica capaz de hidrolisar os substratos PNPP (61,2 U/mg), ATP (19,7 U/mg), e o pirofosfato (29,7 U/mg), com K0.5 de 0,06 mM, 0,11 mM e 0,08 mM, respectivamente. A enzima exibi cinética "Michaelina" para o pNPP (n=1,2). Para o ATP e o pirofosfato interações sítio-sítio foram observadas com n=1,6 e 2,3, respectivamente. Os íons de magnésio foram potentes estimuladores (K0.5=2,2 mM), enquanto o arsenato e o fosfato foram potentes inibidores competitivos. A atividade PNPPase foi inibida pelo EDTA, mas não pelo cálcio, levamisol, zinco, cobalto e phidroximercuribenzoato. A entalpia de inativação térmica foi da ordem de 77,5 kcal.mol- 1. Os resultados sugerem que a produção da fosfatase ácida ligada à membrana representa um mecanismo de solubilização do fosfato mineral aumentando a disponibilidade de nutrientes para as plantas / Abstract: The ability of endophytic bacteria in solubilizing inorganic phosphate is of great interest by microbiologists since phosphatases are responsible for catalyzing the hydrolysis of organic compounds producing soluble phosphorus. Thus, the membranebound acid phosphatase (MBAP) was obtained from Enterobacter sp. isolated from Cattleya walkeriana (Orchidaceae) roots and identified by the 16S rRNA gene sequencing analysis. The enzyme expression was demonstrated to be strictly regulated by phosphorus (optimal expression at 7 mM). The enzyme was obtained by centrifugation at 100.000g for 1 h at 4ºC. The apparent optimal pH (3.5) was not affect by p-Nitrophenyl phosphate concentration. At pH 3.5, the enzyme showed a broad substrate specificity hydrolyzing different substrates such as PNPP (61.2 U/mg), ATP (19.7 U/mg), and pyrophosphate (29.7 U/mg), with K0.5 values of 0.06 mM, 0.11 mM and 0.08 mM, respectively. The hydrolysis of PNPP by the enzyme exhibited "Michaelian" kinetics with n= 1.2. For ATP and pyrophosphate site-site interactions were observed with n= 1.6 and 2.3, respectively. Although magnesium ions were stimulatory (K0.5= 2.2 mM), arsenate and phosphate were a powerful competitive inhibitor. The PNPPase activity was inhibited EDTA but not by calcium, levamisole, zinc, cobalt and phydroxymercurybenzoate. The ΔH for thermal inactivation was 77.5 kcal.mol-1. Our results suggest that the production of a membrane-bound acid phosphatase might be one mechanism of mineral phosphate solubilization turn it's nutrients availability to plants / Orientador: João Martins Pizauro Junior / Coorientador: Cecília Maria Costa do Amaral / Banca: Mariana Carina Frigieri / Banca: Jesus Aparecido Ferro / Mestre
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Etudes de systèmes organométalliques et biologiques par des méthodes hybrides mécanique quantique/mécanique moléculaire

Retegan, Marius 27 February 2009 (has links) (PDF)
Ces dernières années, les méthodes hybrides QM/MM combinant la mécanique quantique (QM) et la mécanique moléculaire (MM) se sont revélées des méthodes de choix pour l'étude de systèmes chimiques et biochimiques contenant plus d'une centaine d'atomes. Nous avons mis en évidence les apports et difficultés liés à leur utilisation à travers des systèmes variés: modélisation de ligands phosphines, réactivité d'une protéine de type acide phosphatase pourpre, modélisation de l'interaction protéine-ligand.
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Studies on the phenotype and function of osteoclasts using osteopetrotic and rachitic animal models /

Hollberg, Karin, January 2007 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.
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Comportamento bioquímico e ultraestrutural de trichoderma harzianum em resposta a presença de cádmio / Ultrastructural and biochemical behavior of Trichoderma harzianum in response to cadmium

Adriana de Freitas Lima 28 February 2008 (has links)
Considerando o potencial biotecnológico do fungo Trichoderma harzianum no processo de metabolização de compostos xenobióticos e sua resistência a metais pesados, o presente trabalho teve como finalidade estabelecer conhecimentos bioquímicos e ultraestruturais associados ao processo de remoção de cádmio. O microrganismo foi cultivado em meio contendo diferentes concentrações de cádmio: 1mM, 2mM e 3mM. O perfil de crescimento foi estabelecido em função da biomassa produzida, do consumo de glicose e fosfato, conteúdo intracelular de polifosfato, atividade das enzimas fosfatases ácida e alcalina, perfil de proteínas totais e remoção do metal. Os resultados obtidos sugerem efeitos do metal sobre o crescimento do organismo em diferentes meios de cultura. O crescimento em meio padrão revela a tolerância do organismo frente a altas concentrações de cádmio, e que tal cultivo induz variações no consumo de glicose e atividade das fosfatases. A utilização da microscopia óptica revelou variação na morfologia do organismo como resposta a variação do meio de cultivo e da presença e ausência do metal. Modificações relativas a processo de ramificação, textura e espessura das hifas foram visualizadas. Os aspectos ultraestruturais através de varredura demonstraram que T. harzianum cultivado na presença de cádmio apresentou variações associadas a eletrondensidade, densidade micelial, maior ramificação e menor número de clamidósporos. A análise do perfil de proteínas totais revelou que o cultivo em cádmio induziu a diminuição do conteúdo de proteínas dependendo da concentração. O isolado foi capaz de acumular polifosfato, e a presença do metal induziu a degradação do polímero em função da concentração. A remoção de cádmio do meio foi avaliada, revelando variação em função da concentração. Os resultados demonstram o efeito do cádmio sobre T. harzianum, pela primeira vez, e demonstram o potencial do microrganismo em acumular polifosfato e sua possível aplicação na remediação de metais pesados / Considering the biotechnological potential of Trichoderma harzianum in the xenobiotic metabolization and its resistance to heavy metals, the aim of this work was to evaluate the utrastructural and biochemical behavior related to cadmium tolerance and removal. The microorganism was grown in different media, containing 1mM, 2mM and 3mM of cadmium. Aspects of the growth profile was obtained by biomass production, glucose consumption, acid and alkaline phosphatase activities, morphology by optical microscopy, ultrastructure by scanning electron microscopy, total protein profile, polyphosphate acumulation and metal removal were evaluated. The results obtained revealed the inhibitory effects of the heavy metal on the microbial growth and the aspects of the tolerance to cadmium. The glucose consumption and the enzymes activities were also affected by cadmium and its different concentrations. The morphological analysis revealed variations related to hyphae thickness, branching pattern, texture and homogenity, electrondensity, and presence of granular structures. The ultrastructural aspects revealed alterations related to cell electrondensity, mycelia density, branching pattern and reduced chlamidospores number. The grown in presence of the metal induced a reduction in the total protein content related to cadmium concentration. The isolate was able to accumulate polyphosphate, and its grown in cadmium induced the polymer degradation. The cadmium removal was observed and revealed variations related to metal concentrations. The results for the first time revealed the effects of cadmium on T. harzianum polyphosphate accumulation and its potential application in the metal remediation
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Indução da expressão e caracterização de uma fosfatase ácida ligada à membrana produzida por Burkholderia sp

Rombola, Tiago Henrique [UNESP] 11 August 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-11Bitstream added on 2014-06-13T20:56:20Z : No. of bitstreams: 1 rombola_th_me_jabo.pdf: 290913 bytes, checksum: 08f244b9cd35a229582ac7563c4b4ff9 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Espécies de Burkholderia filogenéticamente distantes do complexo B. cepacia, são versáteis solubilizadores de minerais insolúveis, através da produção de ácidos, viabilizando nutrientes para as plantas. Descrevemos a purificação e caracterização da fosfatase ácida ligada à membrana, produzida pela bactéria do gênero Burkholderia, isolada de solo agrícola em Ponta grossa-PR-BRASIL, e identificada através da análise do 16s rDNA. A expressão da enzima se mostrou estritamente dependente ao fósforo (expressão ótima a 5 mM). A enzima ligada à membrana foi purificada por ultracentrifugação a 100.000g por 1 hora a 4°C e testada com atividade enzimática para p-nitrofenilfosfato (PNFF) e Pirofosfato. O pH ótimo da enzima foi 6 e não foi afetado pela concentração de PNFF. Em pH 6 a hidrolise do PNFF seguiu os seguintes parâmetros cinéticos com n=1.5, Vm= 103.8 U.mg-1 e K0,5=0,06 mM em uma faixa de 0,003 e 10 mM de PNFF. Estudos do pH sobre os parâmetros cinéticos demonstraram 26 pontos de variação na faixa de 3,5 a 6 e em seguida diminui até pH 8 enquanto K0,5 não mostrou variação nesta faixa. O H para hidrólise do PNFF foi de 5,74 kcal.mol-1. A atividade PNFFase foi inibida pelo arsenato e Cálcio, mas não por levamisol, EDTA, zinco e cobalto. A hidrolise do pirofosfato na presença de 2 mM de MgCl2 seguiu os parâmetros cinéticos de Michaelis-Menten” com Km= 0.142 mM e Vm= 237 U.mg-1.Os resultados sugerem que a produção da fosfatase ácida ligada à membrana pode ser um mecanismo de solubilização de fosfato mineral por essa bactéria. / Burkholderia species phylogenetically greatly distant from the B. cepacia complex species are versatile organisms that solubilize insoluble minerals through the production of acids, increasing the availability of nutrients to plants. Here we describe the purification and characterization a membrane-bound acid phosphatase produced by bulkholderia isolated from an agricultural soil in Ponta grossa-PR-BRASIL and identified through analysis of the 16S rDNA gene. The expression of this enzyme was demonstrated to be strictly regulated by phosphorus (optimal expression at 5 mM). The membrane bound enzyme was purified by centrifugation at 100.000g for 1 h at 4ºC and the enzyme was assayed for p-Nitrophenyl phosphatase (PNPPase) and pyrophosphatase activities. The optimal pH (6.0) was not affect by p-Nitrophenyl phosphate concentration. At pH 6.0 the hydrolysis of PNPP following a cooperative kinetics with n= 1.5, Vm= 103.8 U.mg-1 and K0.5= 0.60 mM in the range between 0.003 and 10 mM. Studies of pH effects on kinetics parameters revealed a 26-folds variation in the range of pH 3.5 to 6 following decreases until pH 8.0, wile K0,5 and cooperativity did not varied considerably in this range. The H for hydrolysis of PNPP was 5,74 kcal.mol-1. PNPPase activity was inhibited by arsenate, phosphate and calcium, but not for levamisole, EDTA, zinc, magnesium and cobalt. The hydrolysis of pyrophosphate in presence of 2 mM MgCl2 follows Michaelis-Menten” kinetics with Km= 0.142 mM and Vm= 237 U.mg-1. Our results suggesting that the production of membranebound acid phosphatase might be one mechanism of mineral phosphate solubilization by this genus of Bacterium.
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Estudo das fosfatases ácidas e fosfatase alcalina na saliva e no soro de crianças

Chaves Neto, Antonio Hernandes [UNESP] 16 December 2005 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-12-16Bitstream added on 2014-06-13T20:56:53Z : No. of bitstreams: 1 chavesneto_ah_me_araca.pdf: 216462 bytes, checksum: a077ffffb43a7f52121fc844bcf5ba50 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A saliva é coletada através de métodos simples e não invasivos, além de ser facilmente armazenada. A coleta não-traumática é atrativa especialmente para crianças e quando repetidas coletas são requeridas. A desvantagem da saliva como uma ferramenta de diagnóstico é a variabilidade, que ocorre em decorrência dos fatores fisiológicos e do modo de coleta. Numa primeira etapa o trabalho teve por objetivo estudar as atividades das enzimas fosfatase alcalina (FAlc), fosfatase ácida total (FAT) e fosfatase ácida resistente ao tartarato (TRAP) na saliva total não estimulada de crianças, investigando as influências de fatores como sexo, faixa etária e horário de coleta, bem como a correlação das enzimas com a taxa de fluxo salivar. Nesta etapa, 120 crianças saudáveis de ambos os sexos, nas faixas etárias de 1-5 e 6-12 anos de idade tiveram as amostras de saliva coletada entre 8:00-10:00 horas ou entre 14:00-16:00 horas. A segunda parte do trabalho teve por objetivo avaliar a correlação das atividades enzimáticas da FAT, TRAP, proteína tirosina fosfatase de baixa massa molecular relativa (PTP-BMr) e FAlc na saliva e no soro de crianças, além de analisar a influência do sexo e da faixa etária na atividade das enzimas, no soro e na saliva total. Para tanto 32 crianças de ambos os sexos, nas faixas etárias de 1-5 anos e 6-12 anos de idade tiveram as amostras de saliva e sangue coletadas entre 8:00-10:00 horas. Os resultados da primeira etapa sugerem que as atividades da FAT, TRAP e FAlc são influenciadas, de formas distintas, pelos fatores sexo, faixa etária e horário de coleta e que não existe correlação entre as atividades das enzimas e a taxa de fluxo salivar. / Saliva can be collected by simple, non-invasive methods and is easily stored. The non-traumatic collection is specially appealing for children and when repeated collections are required. The main disadvantage of the saliva as a diagnosis tool is the variability that happens due to the physiologic factors and dependence on mode of the collection. In a first stage the work had for objective to study the activities of the enzymes alkaline phosphatase (ALP), total acid phosphatase (TAP) and tartrate-resistant acid phosphatase (TRAP) in the whole unstimulated saliva of children, investigating the influences of factors as sex, age group and time of collection, as well as the correlation of the enzymes with the salivary flow rate. In this stage, 120 healthy children of both sexes, in the age groups of 1-5 and 6-12 years of age had the saliva samples collected between 8:00-10:00 hours or between 14:00-16:00 hours. In a second stage, the work had for objective to evaluate the correlation of the enzymatic activities of TAP, TRAP, low molecular weight protein tyrosine phosphatase (LMW-PTP) and ALP in the saliva and in the children's serum, besides analyzing the influence of the sex and of the age group in the activity of the enzymes, in the serum and in the whole unstimulated saliva. For so much 32 children of both sexes, in the 1-5 year-old age groups and 6-12 years of age had the saliva samples and blood collected between 8:00-10:00 hours. The results of the first stage suggest that the activities of TAP, TRAP and ALP are influenced, in different ways, for the factors sex, age group and time of collection and that correlation doesn't exist between the activities of the enzymes and the salivary flow rate.

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