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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.
191

Map-based cloning of the NIP gene in model legume Medicago truncatula.

Morris, Viktoriya 05 1900 (has links)
Large amounts of industrial fertilizers are used to maximize crop yields. Unfortunately, they are not completely consumed by plants; consequently, this leads to soil pollution and negative effects on aquatic systems. An alternative to industrial fertilizers can be found in legume plants that provide a nitrogen source that is not harmful for the environment. Legume plants, through their symbiosis with soil bacteria called rhizobia, are able to reduce atmospheric nitrogen into ammonia, a biological nitrogen source. Establishment of the symbiosis requires communication on the molecular level between the two symbionts, which leads to changes on the cellular level and ultimately results in nitrogen-fixing nodule development. Inside the nodules hypoxic environment, the bacterial enzyme nitrogenase reduces atmospheric nitrogen to ammonia. Medicago truncatula is the model legume plant that is used to study symbiosis with mycorrhiza and with the bacteria Sinorhizobium meliloti. The focus of this work is the M. truncatula nodulation mutant nip (numerous infections and polyphenolics). The NIP gene plays a role in the formation and differentiation of nodules, and development of lateral roots. Studying this mutant will contribute knowledge to understanding the plant response to infection and how the invasion by rhizobia is regulated. Previous genetic mapping placed NIP at the top of linkage group 1 of the M. truncatula genome. A NIP mapping population was established with the purpose of performing fine mapping in the region containing NIP. DNA from two M. truncatula ecotypes A17 and A20 can be distinguished through polymorphisms. Positional mapping of the NIP gene is based on the A17/A20 genetic map of M. truncatula. The NIP mapping population of 2277 plants was scored for their nodulation phenotype and genotyped with flanking molecular genetic markers 146o17 and 23c16d, which are located ~1.5 cM apart and on either side of NIP. This resulted in the identification of 170 recombinant plants, These plants' DNAs were tested further with different available genetic markers located in the region of interest, to narrow the genetic interval that contains the NIP gene. Segregation data from genotyping analysis of recombinant plants placed NIP in the region between 4L4 and 807 genetic markers.
192

Design considerations in high-throughput automation for biotechnology protocols

Unknown Date (has links)
In this dissertation a computer-aided automation design methodology for biotechnology applications is proposed that leads to several design guidelines. Because of the biological nature of the samples that propagate in the automation line, a very specific set of environmental and maximum allowed shelf time conditions have to be followed to obtain good yield. In addition all biotechnology protocols require precise sequence of steps, the samples are scarce and the reagents are costly, so no waste can be afforded. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
193

Attempts to clone the Limulus ependymin gene, and the effects of a human ependymin peptide on human SHSY neuroblastoma cells

Arca, Turkan 04 May 2005 (has links)
ABSTRACT This thesis was divided into two parts. The purpose of part I was to clone and sequence the full-length ependymin gene from the invertebrate Limulus polyphemus, or portions of the gene, and to use RT-PCR to determine whether expression of this gene increases during leg regeneration. PCR was chosen as the method for obtaining the gene due to the success our lab had previously characterizing several ependymin genes using this approach. Three sets of primers were designed based on the conserved domains between teleost fish and three invertebrate ependymin sequences. “Sea primers" were designed based on the nucleotide sequence of the sea cucumber H. glaberrima for each conserved domain, and these primers produced all four of the expected size amplicons with Limulus DNA, but surprisingly only one such band with the sea cucumber Sclerodactyla briareus. The consensus primers (con-primers) were designed based on the most conserved nucleotide among all known ependymin species at each particular position in the conserved domains. Primers designated“5-11 primers" were designed based on the absolutely conserved domains among the three known invertebrate ependymins. Neither con-primers nor 5-11 primers produced any bands of the expected size; this was true for both species of DNA. One very strong band was produced using“5-11" primer pair 6/10 with both species. One of the bands from this reaction from Limulus was cloned and sequenced, and showed a very strong homology (88% over 292 bp) with mouse FGF-14, a neurotrophic factor involved in mouse neurogenesis. The expression of this gene during leg regeneration will be tested in future experiments. Limulus GAPDH was also cloned and sequenced, and a genomic intron was identified for the first time in this study. This Limulus housekeeping gene will be used in future studies for gene expression comparisons. The purpose of part two of this thesis was to study the up-regulation of growth-related genes induced by treatment of a human neuroblastoma SH-SY5Y cell line with a human ependymin peptide mimetic (hEPN-1), in an attempt to help provide a basis for using human EPN mimetics as therapeutics in stroke and neurodegenerative diseases. The sequence of this mimetic is derived from an area of human MERP-1 analogous to goldfish mimetic CMX-8933. The human mimetic was previously found to up-regulate growth related genes L-19, EF-2 and ATP Synthase in the mouse neuroblastoma cell line Nb2a (Saif, 2004). The expression levels of genes encoding ribosomal proteins and ribosomal RNA were studied using RT-PCR as hallmarks of proliferating cells. hEPN-1 was found to increase the expression of the nuclear-encoded ribosomal proteins S-19 and S-12, an average of 2.76 fold and 1.74 fold, with statistically significant p-values of 0.031 and 0.015 (<0.05), respectively. The expression levels of nuclear-encoded 5.8S ribosomal RNA (p = 0.018) and the mitochondrial-encoded 16S RNA (p = 0.046) were found to be increased an average of 14.04 fold and 3.91 fold, respectively. Thus, human ependymin mimetic hEPN-1 appears to stimulate growth-related genes, a property which can be useful to regenerate neuronal tissue after injury.
194

The analysis of cDNA sequences: an algorithm for alignment.

January 1997 (has links)
by Lam Fung Ming. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 45-47). / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter CHAPTER 2 --- BACKGROUND --- p.4 / Section 2.1 DNA Cloning --- p.5 / Section 2.1.1 Principles of cell-based DNA cloning --- p.5 / Section 2.1.2. Polymerase Chain Reaction --- p.8 / Section 2.2 DNA Libraries --- p.10 / Section 2.3. Expressed Sequence Tags --- p.11 / "Section 2.4 dbEST - Database for ""Expressed Sequence Tag""" --- p.13 / Chapter CHAPTER 3 --- REDUCTION OF PARTIAL SEQUENCE REDUNDANCY AND CDNA ALIGNMENT --- p.15 / Section 3.1 Materials --- p.15 / Section 3.2 Our Algorithm --- p.16 / Section 3.3 Data Storage --- p.24 / Section 3.4 Criterion of Alignment --- p.27 / Section 3.5 Pairwise Alignment --- p.29 / Chapter CHAPTER 4 --- RESULTS AND DISCUSSION --- p.32 / Chapter CHAPTER 5 --- CONCLUSION AND FUTURE DEVELOPMENT --- p.42 / REFERENCES --- p.45 / APPENDIX --- p.i
195

Clonagem do gene de uma amilase termoestável em E.coli E B. subtilis. Estudo de sua expressão em E. coli / Cloning and expression of a termostable amylase in E.coli and B. subtilis. Study of the expression in E. coli

Silva, Enny Fernandes 17 February 1989 (has links)
O DNA de plasmídeos naturais de uma cepa de B. stearothermophilus foi clivado com a enzima de restrição Hind III e os fragmentos resultantes foram ligados com T 4 DNA ligase ao vetor pBR 322 (Bolívar et. al., 1977) que já havia sido previamente tratado com Hind III e fosfatase alcalina. A terça parte desta mistura de ligação foi usada para transformar células de E. coli HB 101. Foram obtidos cerca de 3.500 transformantes, dos quais 46% eram recombinantes. Duas cepas que mostraram caracter amilolítico consideravelmente maior que a doadora do gene continham o plasmídeo pBR 322 com uma inserção de 5.4 Kb. O mapa de restrição, tratamento com a enzima BAL 31 e, sucessivas subclonagens (Silva, E.F. et. al.,1986)mostraram que o gene que codifica e expressa a enzima amilolítica está contido em um fragmento de 2 Kb. A enzima produzida pelas células transformadas tem peso molecular de 60.000, é estabilizada por Ca+2, tem um ótimo de temperatura de 72ºC e retém 90% da atividade original após aquecimento a 85°C por 1 hora. Estes resultados, em conjunto com a análise dos produtos de hidrólise desta enzima em cromatografia de papel, sugerem que foi clonada a alfa - amilase de B. stearothermophilus em células de E. coli. Células de duas cêpas de B. subtilis, IA 289 e BD 241 foram transformadas respectivamente com os plasmídeos p USP 33.2 (Silva, E.F. et al., 1986;1987) e p BU 217 ami 2 (Silva, E.F. & Pueyo, M.T.,1988) para produzir em ambos os casos colônias fortemente amiloliticas. Os mecanismos pelos quais as 2 cêpas passaram a apresentar o fenótipo AMY + , são provavelmente diferentes. / The DNA of natural plasmids. from a B. stearothermophilus strain was cut with Hind III endonuclease and the resulting fragments were joined with T4 DNA ligase to the vector pBR 322 (Bolivar et al. , 1977), which had previously been treated with Hind III and alkaline phosphatase. One-third of the ligation mixture was used to transform E. coli HB 101 cells. It was obtained about 3.500 transformants, which included 46% recombinans. Two strains displayng amylolytic act ivity remarkably higher than the donor gene strain, harbored the plasmid pBR 322 with an insertion of 5.4 kb. The restriction map, Bal 31 treatment and successive subcloning (Silva, E.F, et al.,1986) showed that the entire gene which codifies and allows the expression of the amylolytic enzyme is contained in a 2 Kb fragment. The enzyme has a molecular weight of 60.000, is stabilized by Cata, has a temperature optimum at 72°C and retains 90% of the original activity after heating for 1h at 85°C. These features, together with the analysis of hydrolysis produts carried on paper chromatography , suggests that we succeded in cloning the amylase from B. stearothermophilus in E. coli cells. Cells from two B. subtilis strains, IQ 289 and BD 241 were transformed with the plasmid sp USP 33.2 (Silva E. F. et al., 1986 1987) and pBU 271 ami 2 (Silva, E. F. & Pueyo, M.T., 1988) , and produce in both strains, amyiolytic colonies. The methods in which the two strains have got the AMY + fenotype, may be very different.
196

Partial Characterization Of Plasmodium Falciparum Protein Kinase ABCk2 (PfABCk2)

Khalid, Muhammad 27 June 2018 (has links)
Malaria is a major threat to the public health worldwide as it is affecting populations in tropical and subtropical areas globally. Among those populations are around 40% of pregnant women and children who are susceptible to this disease. Plasmodium falciparum is the most lethal agent that causes malaria in human. Currently, there is drug resistance against antimalarial drugs in parasite against treatment of malaria infections, it is essential to search for new drug targets in order to find cure and alleviate suffering of human population. There are approximately 100 protein kinases in P. falciparum that are involved in phosphorylation of asexual blood stage. Hence, the phosphorylation plays an important part in the development of different stages of malarial parasites. Due to their significance in the parasite life cycle, one of the protein kinase of P. falciparum belongs to the ABC-1 family of proteins. PfABCK2 can be a therapeutic target due to its higher expression during the late schizont stage of blood stage form. The bioinformatic analysis and preliminary results of PfABCK2 showed the heterologous expression of this protein. Hence, the gene of PfABCk2 was ligated into pET21a+ vector with His-tag at C-terminus and transformed into BL-21 (DE3) competent cells that were verified through Miniprep and DNA sequencing. Furthermore, this gene construct is utilized to heterologous express this protein with IPTG and afterwards purified the recombinant protein kinase using nickel affinity chromatography as shown on 10% SDS-PAGE with the expected 36 kDa protein band. Therefore, the aim of this study is to partially characterize PfABCK2 protein kinase utilizing molecular cloning, heterologous express and protein kinase activity assay.
197

The molecular and functional characterization of soluble Ifnar-2

Hardy, Matthew Philip,1974- January 2001 (has links)
Abstract not available
198

Towards cloning Yd2 : a barley resistance gene to barley yellow dwarf virus

King, Brendon James. January 2001 (has links) (PDF)
Errata attached to inside front cover. Bibliography: leaves [156-188]
199

Ex vivo expansion of human haemopoietic progenitor cells

Haylock, David Norman. January 2001 (has links) (PDF)
"December 2001." Includes bibliographical references (leaves 178-225) Focuses on the ex vivo growth of human haemopoietic progenitor cells with the objective of defining culture conditions for generating myeloid post-progenitor cells for therapy
200

Ex vivo expansion of human haemopoietic progenitor cells / by David Norman Haylock.

Haylock, David Norman January 2001 (has links)
"December 2001." / Includes bibliographical references (leaves 178-225) / xviii, 225 leaves : ill. (some col.), plates, charts ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Focuses on the ex vivo growth of human haemopoietic progenitor cells with the objective of defining culture conditions for generating myeloid post-progenitor cells for therapy / Thesis (Ph.D.)--University of Adelaide, Dept. of Molecular Biosciences, 2001

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