Dissertations / Theses on the topic 'PU61'

El curso de Fotografía Publicitaria va dirigido a dos carreras de la Facultad de Comunicaciones, la carrera de Comunicación y Publicidad y la carrera de Comunicación Audiovisual y Medios Interactivos. El curso es de carácter teórico-práctico y desarrolla en el alumno las competencias generales de Pensamiento Innovador y específicas de Análisis e Interpretación de la Realidad La fotografía publicitaria es un área de la fotografía destinada a exaltar las cualidades de un producto o servicio de modo que se incentive su consumo. En este curso los estudiantes aprenderán a convertir conceptos en imágenes y a dominar la técnica fotográfica en estudio.

El curso de Fotografía Publicitaria va dirigido a dos carreras de la Facultad de Comunicaciones, la carrera de Comunicación y Publicidad y la carrera de Comunicación Audiovisual y Medios Interactivos. El curso es de carácter teórico-práctico y desarrolla en el alumno las competencias generales de Pensamiento Innovador y Análisis e Interpretación de la Realidad La fotografía publicitaria es un área de la fotografía destinada a exaltar las cualidades de un producto o servicio de modo que se incentive su consumo. En este curso los estudiantes aprenderán a convertir conceptos en imágenes y a dominar la técnica fotográfica en estudio.

Curso de especialidad en la carrera de Comunicación y Publicidad de carácter práctico-teórico dirigido a los estudiantes del noveno ciclo, que busca desarrollar las competencias generales de Pensamiento crítico y las competencias específicas de Análisis e interpretación de la realidad, Gestión de recursos y Creatividad. Actualmente la publicidad se está reinventando, dado que los medios de comunicación cada vez están más saturados de mensajes y en un mar de productos/servicios que se ofertan diariamente. Las marcas apuntan a llegar a los consumidores cuando lo necesitan a través de una comunicación bidireccional. Por ello enfocan sus estrategias en dos puntos clave: estableer una estrucutura fuerte de marca que las diferencie del resto (branding) y difundir el mensaje através de un mix de medios que amplifique el alcance, llegando en el momento preciso que el consumidor quiera recibir o necesite la información (content marketing).

Curso de especialidad en la carrera de Comunicación y Publicidad, de carácter teórico-práctico, dirigido a los estudiantes de octavo ciclo. Busca desarrollar la competencia general de pensamiento crítico y las competencias específicas de creatividad y de análisis e interpretación de la realidad. En este caso, el alumno revisa con minuciosidad los conceptos semióticos expresados en texto o imágenes que lo llevan a comprender los recursos para la elaboración de mensajes poderosos. Este curso es una profundización de conceptos básicos estudiados en el curso de Semiótica y una aproximación sistemática a un análisis integral de la comunicación con fines publicitarios.

Curso de especialidad en la carrera de Comunicación y Publicidad, de carácter teórico-práctico, dirigido a los estudiantes de octavo ciclo. Busca desarrollar la competencia general de pensamiento crítico y la competencia específica de análisis e interpretación de la realidad. En este caso, el alumno revisa con minuciosidad los conceptos semióticos expresados en texto o imágenes que lo llevan a comprender los recursos para la elaboración de mensajes poderosos. Este curso es una profundización de conceptos básicos estudiados en el curso de Semiótica y una aproximación sistemática a un análisis integral de la comunicación con fines publicitarios.

Curso general de la Facultad de Comunicaciones, de carácter teórico, dirigido a los estudiantes de las carreras de Comunicación y Publicidad, Comunicación y Marketing (3er ciclo), Comunicación e Imagen Empresarial (4to ciclo) y Comunicación Audiovisual y Medios Interactivos (mención propia en Publicidad). Propósito: La vertiginosa evolución de las comunicaciones y el empoderamiento del consumidor conducen hoy a los fabricantes de productos y servicios a desarrollar modelos de publicidad cada vez más efectivos. Lograr que los compradores potenciales, encuentren, conozcan y se habitúen a sus productos y servicios es una de las principales tareas de la publicidad. Otro de los roles de la publicidad es generar soluciones creativas en función al conocimiento profundo de las personas, del perfil de la marca y de las características de los medios. "(...)La publicidad rodea nuestras vidas, nos persigue por todas partes, pero a pesar de estar presente y mostrarse tanto, oculta a los ojos del espectador cuáles son sus claves profesionales, cómo funciona, por qué funciona." Marçal Moliné. La Comunicación Activa (1997).

El curso Comportamiento del Consumidor realiza análisis constantes sobre las razones y situaciones que influyen en el consumo de un individuo o grupo. Por esta razón, a lo largo del curso, el estudiante identifica y comprende los principales procesos que se generan en la mente del consumidor con la finalidad de conocer la forma en la que evalúa productos y marcas. Este conocimiento es de total utilidad para todo comunicador, permitiéndole conocer a profundidad el comportamiento del consumidor. El curso de Comportamiento del Consumidor ha sido diseñado con el propósito de permitir al futuro comunicador desarrollar su capacidad de análisis, indispensable para que elabore futuras estrategias de comunicación. El curso contribuye directamente al desarrollo de la competencia de Pensamiento Crítico (general-UPC) a un nivel 2 y de la competencia específica (Facultad de Comunicaciones) de Estrategia Comunicacional a un nivel 1.

Comportamiento del Consumidor es un curso general en la Facultad de Comunicaciones, de carácter teóricopráctico dirigido a los estudiantes del 3er ciclo, que busca desarrollar la competencia general Pensamiento crítico y la competencia específica de Estrategia comunicacional Desarrollar la capacidad de análisis es indispensable para que el estudiante elabore futuras estrategias de comunicación. Por esta razón, a lo largo del curso el estudiante comprende las necesidades y motivaciones de diferentes individuos o grupos, identifica los principales factores que influyen en su comportamiento y conoce la forma en la que se evalúan productos y se toman decisiones de consumo. Este conocimiento sirve como insumo primario que permite conocer a profundidad el comportamiento del consumidor.

comunicador reconozca la perspectiva de la empresa desde un enfoque altamente analítico y competente, siendo importante que conozca todo el manejo en la creación y gestión de productos antes de preparar la campaña de comunicación. Debido a que las estrategias publicitarias deben estar alineadas a las estrategias de marketing, el publicista debe contar con un conocimiento sólido sobre las variables inmersas en este. Propósito: Curso de especialidad Gerencia de Producto en la carrera de Comunicación y Publicidad de carácter teóricopráctico, dirigido a los estudiantes del sexto ciclo, que busca desarrollar la Competencia General de Pensamiento Innovador y la Competencia de Facultad de Gestión de Recursos.

Curso de especialidad Gerencia de Producto en la carrera de Comunicación y Publicidad de carácter teóricopráctico, dirigido a los estudiantes del sexto ciclo, que busca desarrollar la competencia general de pensamiento innovador y la competencia específica de gestión de recursos. En un entorno de alto nivel de competitividad como el que rige en la actualidad es prioritario que el comunicador reconozca la perspectiva de la empresa desde un enfoque altamente analítico y competente, siendo importante que conozca todo el manejo en la creación y gestión de productos antes de preparar la campaña de comunicación. Debido a que las estrategias publicitarias deben estar alineadas a las estrategias de marketing, el publicista debe contar con un conocimiento sólido sobre las variables inmersas en este.

Biomolecular condensates act as indispensable membrane-less organelles for intracellular organization and regulation of biochemical reactions. Proteins and RNAs are known to phase separate into condensates, however the sequence domains that encode this process remain unclear. By means of computational tools and predictions, I systematically analysed the sequences of the human and yeast proteomes for phase separation ability. Furthermore, I experimentally evaluated the sequence domains of the yeast protein Pub1. My findings report that RNA-binding domains (RBDs) and prion-like domains (PrLDs) play different roles in the phase separation process. While one PrLD can lead the assembly, a combination of RBDs modulate the dynamicity of the condensate. The high interacting capacity of the PrLD explains the ability to recruit molecules into condensates but it also compromises homeostasis. This work sheds light on the principles behind formation and regulation of membrane-less organelles.
Els condensats biomoleculars actuen com a orgànuls sense membrana, organitzant el funcionament intern de la cèl·lula i regulant les reaccions bioquímiques que hi tenen lloc. Proteïnes i ARNs es separen en una fase diferent formant aquests condensats, però els dominis de les seves seqüències que propicien aquest procés encara no són clars. A través d’eines computacionals i de prediccions, he analitzat la habilitat de les seqüències del proteoma humà i de llevat de formar aquesta nova fase. A més, he avaluat experimentalment els dominis de la seqüència de Pub1, una proteïna de llevat. Els meus resultats indiquen que els dominis d’unió a ARN (RBDs) i els dominis similars a prions (PrLDs) tenen funcions diferents en el procés de separació de fases. Mentre que un PrLD pot liderar-ne la formació, diversos RBDs modulen les dinàmiques dintre del condensat. L’elevada capacitat d’interacció que tenen els PrLDs explica l’habilitat de reclutar molècules per formar condensats, però alhora compromet els equilibris i estabilitat cel·lulars (homeòstasi). La meva investigació revela informació sobre els principis que governen la formació i regulació d’orgànuls sense membrana.

La proteine pus1 de s. Cerevisiae catalyse l'isomerisation de l'uridine en pseudouridine () a differentes positions de certains arnt. Le gene pus1 a ete clone et hyperexprime chez e. Coli avec 6 histidines en son extremite n-terminale, afin de purifier aisement la proteine recombinante sur colonne de ni 2 +-nta. En solution, la proteine pus1 recombinante existe majoritairement sous forme de monomeres, mais se presente egalement sous forme d'oligomeres et d'agregats. L'utilisation d'un detergent, le dodecyl--d-maltoside, est indispensable afin de maintenir pus1 en solution, surtout a haute concentration en proteine. L'interaction de pus1 avec differents arnt a ete etudiee. L'affinite de pus1 est generale pour tous les arnt, qu'ils soient substrats (presence d'une uridine cible) ou non. Les constantes d'equilibre de dissociation des complexes pus1 : arnt (k d), mesurees par la technique retention sur filtre de nitrocellulose, varient de 15 nm pour l'arnt v a l substrat, et l'arnt p h e non substrat, a 150 nm pour l'arnt i l e substrat. L'importance de l'architecture de l'arnt a ete etudiee avec des mutants deletes pour les tiges-boucles t et d, ou impliques dans la formation de paires de bases maintenant sa structure tridimensionnelle. Bien que non necessaire pour l'activite de l'enzyme, la presence d'une liaison tertiaire g26-a44, absente dans l'arnt i l e, est un element important pour la reconnaissance de l'arnt avec une haute affinite (k d = 15 nm). La presence de cette liaison tertiaire augmente la vitesse d'association de l'arnt a l'enzyme d'un facteur 100 environ, resultant en une diminution globale de la constante d'equilibre de dissociation. Ces constantes ont ete mesurees par la technique de resonance des plasmons de surface. Nous avons de plus montre par spectroscopie atomique d'absorption, que la proteine recombinante pus1 contient un atome de zinc par monomere. Pus1 est le premier exemple d'une pseudouridine synthetase contenant un ion zinc. Un enzyme deplete en zinc peut etre obtenu apres dialyse contre l'agent chelatant 1,10-phenanthroline. La perte du zinc resulte en l'inactivation de l'enzyme avec la perte concomitante de sa capacite a lier l'arnt. Elle provoque egalement un changement de structure tridimensionnelle de pus1 (determine par ultracentrifugation analytique), avec un changement mineur de son organisation interne (determine par uvcd, ftir ou fluorescence). Nos resultats sont en accord avec un role structural pour le zinc, qui maintiendrait l'association entre des domaines structuraux de pus1. Enfin, dans un extrait de levure, pus1 existe sous deux formes reconnues par les anticorps polyclonaux anti-pus1 (technique de western blot) et de poids moleculaires autour de 63kda,. Une etude precise de la localisation de pus1 par immunocytochimie en microscopie electronique a permis de mettre en evidence la presence de pus1 dans le noyau, essentiellement au niveau de la membrane nucleaire, mais egalement dans la mitochondrie. La presence de pus1 dans ces deux compartiments cellulaires explique vraisemblablement l'existence des deux formes de l'enzyme dans la levure. Ce travail constitue la premiere analyse physicochimique et enzymatique de pus1 et permet de montrer quelles sont les directions a prendre pour les futures recherches la concernant.

The central properties of stem cells are the pluripotency and the capacity of self-renewal. Hematopoietic stem cells (HSCs) posses such common features that allows them to generate all the cells of the hematopoietic compartments, maintaining in the same time the HSC pool. We develop approaches focused on ex vivo HSC expansion through activation by exogenous HOXB4 (human HSCs) or Notch/Dll-4 ligand (murine HSCs). Two independent transcriptomic analyses surprisingly converged toward an increased expression of two genes never identified sofar as crucial for HSC functions: Pumilio1 (Pum1) and Pumilio2 (Pum2). Pum1 and Pum2 are posttranscriptional regulators belonging to the Pumilio-FBF (PUF) family of RNA-binding proteins. Although it was established that the primordial role of PUF proteins is to sustain mitotic proliferation of stem cells in Invertebrates, so far nothing is known about the role of Pum1 and Pum2 in human and murine HSCs.For these reasons, we have investigated the roles and mechanisms of action of Pum1 and Pum2 in murine and human HSCs through shRNA strategy. Pum1 and Pum2 knockdown (KD) in murine HSCs led to a decreased HSC expansion and clonogenic potential ex vivo, associated with an increased apoptosis and a cell cycle arrest in G0/G1 phase. KD of both Pum1 and Pum2 enhanced these effects, suggesting a cooperative effect. Expansion and clonogenic potential of KD Pum1 HSCs were rescued by enforced expression of Pum1 (insensitive to our shRNA), thus validating the specificity of our shRNA. Enforced expression of Pum1 could not rescue the functions of Pum2 KD HSCs, highlighting the non-redundant role of these proteins. Furthermore, when Pum1 or Pum2 KD HSCs were inoculated into lethally irradiated mice to follow the long-term hematopoietic potential, only rare bone marrow cells derived from Pum1 and Pum2 KD HSCs were evidenced after 4 months, contrary to control HSCs. Identical results were obtained with human Pum1 or Pum2 KD HSCs.In conclusion, our results demonstrate the involvement of Pumilio factors in stemness maintenance, expansion and survival of murine and human HSCs. Identification of Pumilio factors and their targets as new regulators of HSCs expansion will allow consider them as new tools for therapeutic perspectives.

Much of the regulation of gene expression occurs at the posttranscriptional level, and much of this regulation is controlled and coordinated by RNA binding proteins (RBPs). Many RBPs have multiple mRNA targets, and the proteins encoded by these targets often share functional relationships, forming posttranscriptional RNA operons. These operons often reflect the function of the RBP, thus determination of the genome-wide targets of RBPs allows insight into their functions.

The PUF family of RBPs is characterized by the presence of an extremely well conserved RNA binding domain, typically consisting of 8 repeats of an RNA binding motif, with each repeat binding to one RNA base. PUF proteins are proposed to have an ancestral role in self-renewal of stem cells and have been shown to affect a number of developmental processes. Human and other vertebrate genomes contain two canonical PUF genes, Pum1 and Pum2, and at the outset of this study there was very little known about functions or targets of either protein, especially Pum1.

In order to identify the genome-wide targets of human Pum1 we used RNA immunoprecipitation followed by microarray, or RIP-Chip, analysis. RIP-Chip allowed us to identify Pum1 target mRNAs in human HeLa cells. We found that there were numerous functional relationships among the proteins encoded by these mRNAs, forming putative RNA operons. Some of these potential operons are progression of cell cycle, cell differentiation and proliferation, and regulation of transcription. We were also able to find a consensus Pum1 binding motif, UGUAHAUA, in the 3' UTRs of Pum1 target mRNAs.

The genome-wide targets of PUF proteins from other species have been previously identified, and by comparing the targets of human Pum1 to targets of Drosophila Pumilio and yeast Puf3, both of which bind to the same RNA sequence as Pum1, we determined that there has been evolutionary rewiring of regulation by Puf proteins. While the PUF RNA binding domain and consensus binding sequence have remained almost identical through evolution, the surrounding protein sequence and the mRNAs bound have changed dramatically, indicating that evolutionary rewiring is occurring in a modular fashion.

After identifying Pum1 associated mRNAs, we went on the study the function of Pum1. Through Pum1 knockdown assays we found that Pum1 enhances decay of target mRNAs, and that this effect is likely due to Pum1 enhancing deadenylation of these mRNAs. We also showed by immunofluorescence that Pum1 protein has a cytoplasmic granular subcellular localization and upon oxidative stress relocates to stress granules but not processing bodies. We were, however, unable to detect any difference in Pum1 mRNA targeting after stress. We were also unable to detect any changes in progression through cell cycle after Pum1 knockdown.

In this study we identified the genome-wide mRNAs associated with Pum1, determined functional relationships among these targets related to the proposed ancestral role of PUF proteins in self-renewal of stem cells, and identified a sequence motif to which Pum1 binds in these mRNAs. We also demonstrated that Pum1 enhances decay of associated mRNAs, and that this effect is likely due to Pum1 enhancing deadenylation of associated mRNAs. These results provide a description of mRNA targets and mechanisms of action of Pum1 proteins, which will provide a strong foundation for future experiments to further explore the functions of the Pum1, especially as they relate to human stem cells.

Dissertation

碩士
國立雲林科技大學
工業化學與災害防治研究所
92
Waste water containing heavy metal are treated by physical method, chemical method, biosorption process, etc. . The biosorption process is better than other methods according to cost consideration. Therefore, the biosorption process for removal of heavy metal（Pb2+） from solutions is chosen in this study. Immobilized Pseudomonas aeruginosa PU21 bead was used as adsorbent. Different concentrations of chitosan and polymer (PEG) were added to alginate to proceed chemical modification with different concentration of Epichlorohydin (ECH) and increase mechanical strength of the bead. The results show that small immobilized bead (3 – 3.5 mm) with 1.5% chitosan + 0.5% PEG + 18% alginate cross-linked by 0.554M ECH had better heavy metal（Pb2+）adsorption efficiency and mechanical strength, when the optimum adsorption conditions (pH = 5 and rpm = 400) were utilized. Different amounts of P. aeruginosa PU21 were added to enhance heavy metal（Pb2+）adsorption. The results reveal that the heavy metal（Pb2+）adsorption capicity increased significantly with the addition of 1％（w/w） P. aeruginosa PU21. Elevation of temperature led to increase in heavy metal（Pb2+）adsorption. The immobilized P. aeruginosa PU21 beads adsorbing heavy metal（Pb2+）were regenerated by 0.1 M HCl solutions to reuse the immobilized P. aeruginosa PU21 beads. The results show that the desorption efficiency was up to 87% and the adsorption efficiency was about 60% after five repeated adsorption and desorption cycles. The result suggests the reusability of immobilized beads. The adsorption data were described by the Langmuir adsorption model with better accuracy. The kinetic analysis shows that the adsorption of Pb2+ was the first order reaction. The thermodynamic property was determined, showing that biosorption of Pb2+ was a spontaneous reaction. Finally, simulation with the mass transfer model determined the effective diffusivity of heavy metal（Pb2+）adsorption by immobilized P. aeruginosa PU21 bead.

Precise regulation of the complex process of gene expression is essential for all aspects of life, and a large degree of this precision is mediated at the posttranscriptional level. The global and individual mechanisms by which posttranscriptional control is coordinated to maintain or alter levels of gene expression as necessary are not fully understood. Identification of the mRNA target sets of individual RNA binding proteins (RBPs) and characterization of the mechanisms by which RBPs regulate the expression of individual mRNAs provide some insight into the global structure of the posttranscriptional environment. However, few studies have integrated these findings into a global model of posttranscriptional control. We have explored the structure and function of the posttranscriptional regulatory system through a combination of global modeling approaches, global studies of mRNA translation and decay, and mechanistic studies of the function of individual RBPs, specifically HuR and Pum1.

By combining RBP-mRNA association data and transcription factor (TF) target data from separate global studies in yeast, we developed an integrated model of gene expression regulation. Evaluation of this model indicates that posttranscriptional regulation may be responsible for substantially greater contributions to the overall gene expression program than transcriptional regulation. Further, we identified a self-regulatory feature of the posttranscriptional network that suggests a `regulators of regulators' structure may be a defining feature of the posttranscriptional control of gene expression.

Additionally, we explored the mechanisms and functional consequences of the dynamic association between an RBP, HuR, and its target RNAs through a combination of modeling and experimental approaches, including polysome profile analysis and global measurement of RNA stability. Our model indicates that changes in total mRNA abundance are insufficient to fully explain the dynamics of association between HuR and its targets, suggesting a role for competition and cooperation with other RBPs. Our findings also indicate that HuR may play a role in inhibition of translation in a dynamic immunological system (T cell activation).

Finally, we performed a mechanistic analysis of the function of the Pum1 RBP and characterized the role of this protein in the translational regulation of several important target mRNAs through the use of luciferase reporter assays. We also provided the first in vivo evidence of a role for specific regions of the Pum1 protein in the mediation of gene expression. However, we were unable to verify previous in vitro reports of a role for Pum1 in the control of translation elongation of verified in vivo mRNA targets, suggesting that Pum1's regulatory function may be context dependent.

Ultimately, the approaches and findings in this study will provide a framework for the development of a global integrated model of posttranscriptional control. Through the iterative development of models and experimentation, hypotheses can be generated and, tested in the laboratory, and the results of these experiments will then further improve the development of the models. An integrated approach of this type will be necessary to fully understand the highly complex and interconnected nature of the gene expression regulatory system.

Dissertation

碩士
靜宜大學
食品營養學系
102
Leuconostoc pseudomesenteroides PU01, isolated from Taiwan brown sugar kefir grains, is a high-producing strain of polysaccharides with ropy material grown on MRS agar plate containing sucrose. In this study, medium components will be optimized by statistical design of experiments for enhance of polysaccharides production. Firstly, Plackett–Burman design was applied to screen the most important factors among 11 components, including sucrose and 10 ingredients of commercial MRS medium. Proteose peptone No.3, sucrose, sodium acetate, and potassium phosphate were found to be the most significant factors for polysaccharides production. Central composite design (CCD) was used further to determine the optimal concentrations of these four important medium components by response surface method (RSM). The optimal medium obtained for maximal production of polysaccharides were 107.58 g/L sucrose, 4.64 g/L sodium acetate, 2.21 g/L potassium phosphate, and without addition of Proteose peptone No.3. After 24-hr cultivation, polysaccharides concentration reached 48.95 g/L with 45.3% yield on sucrose. The polysaccharides production showed 1.8 fold increase over the MRS medium with 108 g/L sucrose.

碩士
靜宜大學
食品營養學系
100
Brown sugar kefir, like milky kefir, is a beverage fermented by lactic acid bacteria and yeasts in Taiwan. This broth has some small bubbles and contains little alcohol. Jelly-like granules, called kefir grains, were formed during cultivation and then were used as starters. Water–soluble polysaccharides were extracted from sugary kefir grains identified as dextrans. In this study, we investigated the effects of different conditions on increase of kefir grains, and estimated the culture parameters of extracellular polysaccharides(EPS) production by strains PU01 isolated from kefir grains. We had collected homemade brown sugar kefir from Taichung, a city of middle Taiwan. Grains(5％) were inoculated to 8％ brown sugar solution and statically cultivated at 25℃. Grains weights increased approximately 1-fold and the pH of broth decreased from 5.2 to 4.2 after 24 h. The yield of polysaccharides extracted by hot water was 0.133g per gram dry weight of grains. Research was conducted for estimation of grains increase by replacing broth with fresh brown sugar solution each day over 6-day period. Factors influencing grains increase, including incubation temperature, brown sugar concentration and initial pH of medium, were studied. The highest grains increase (23.9-fold) was found by cultivation with 300g/L brown sugar solution. The increases of grains were 8.4-fold and 16.8-fold by cultivation at 20℃ and adjusting the initial pH of medium to 10, respectively. When the pH of medium was controlled at 5.2 in a 24–h period, the grains increase was 1.68-fold higher than that by cultivation without pH control. PU01 was a high-producing strain of extracellular polysaccharides(EPS) with ropy material grown on MRS agar plate containing 8％ sucrose or brown sugar. The optimal culture parameters of EPS production were found by cultivation at 25℃ and with initial pH8, respectively. EPS concentration reached 24.43g/L and the yield of EPS to sucrose was 30.53％ by PU01 when cultivated in 8％ sucrose solution for 12 h.

碩士
逢甲大學
化學工程研究所
83
This research investigated the biosorption kinetics of lead, copper, and cadmium ions on the biomass of Pseudomonas arginosa PU21(Rip64). The effects of environmental factors (pH, temperature) and growth conditions (growth phase, initial mercury concentration for cultivation) on the biosorption were also studied. The results showed that at pH 8.0, the resting cells (O.D. 3.25) are able to uptake up to 108 mg Pb/g dry cell , while the inactivated cells absorb 68 mg Pb/g dry cell. Biomass of of Pseudomonas arginosa PU21 (Rip64) has lower adsorption capacities for copper and cadmium ions than that for lead ions. At pH 6.0, the resting cells have the maximum uptake of 34 mg Cu/g dry cell (O.D. 2.0) for copper and 38 mg Cd/g dry cell (O.D. 1.02) for cadmium. The saturation adsorption capacities of inactivated cells (also pH 6.0) for copper and cadmium are 31 mg Cu/g dry cell (O.D. 1.02) and 22 mg Cd/g dry cell (O.D.1.02),respectively. The resting cells hold optimal Pb capacity at the retardation phase, whereas for inactivated cells , the effect of growth state on on Pb adsorption is negligible. For the biosorption of Cd, the best uptake occurs when the biosorbents (both resting cells and inactivated cells) are prepared at the exponential growth phase. The growth phase exhibits no effects on adsorption capacity of Cu, hower. By applying high mercury concentrations (up to 50 mg Hg/L) for the cell cultivation, the adsorption of Pb, Cu, and Cd are not significantly improved, expcept a 27% increase in Cd uptake for resting cells. This suggests that the induction of mer operon by high mercury concentration did not affect the adsorption of copper and lead, only slightly enhances the uptake of cadmium. An increase in pH results in higher saturation adsorption capacity and high metal-biomass affinity.

碩士
國立東華大學
生物技術研究所
96
Antimicrobial peptides (AMPs) play an important role in the innate immune response and host defense mechanism. In recent years, intensive studies have been explored in finding new AMPs and many AMP databases were established. The general characteristics of these functioning AMPs include: positive charge, length of approximately 6 ~ 50 amino acids, amphiphilic, and α-helix. In the present study, the phage displayed random peptide library was used to select the tight binders against the whole cell of P. aeruginosa strain PU21. The biopanning processes were performed for three rounds and the binding capabilities were further estimated by ELISA (Enzyme-Linked ImmunoSorbent Assay). Eight peptides were finally synthesized after sequencing the selected phage genomes and comparing with AMP database. The bacterial growth inhibition (P. aeruginosa PU21 and E. coli DH5α) assays were performed to evaluate the bactericidal activities of the selected peptides. The results indicate that the six of the selected peptides all lack the antimicrobial activities. However, two modified peptides did inhibit the cell growth of E. coli DH5α in the presence of EDTA (0.325 mM).

碩士
逢甲大學
化學工程研究所
85
Our previousestudies demonstrated that mercury-resistant strain Pseudomonas aeruginosa PU21 (Rip64) is capable of effectively adsorbing a variety of heavy metals including Hg, Pb, Cu, and Cd. At pH 5, saturation biosorption capacity of biomass of P. aeruginosa PU21 (Rip64) for Pb, Cu, and Cd was 520, 632, and 327 mmol/g dry cell, respectively. In order to evaluate the feasibility of utilizing the biomass as a practical heavy-metal biosorbent, it is of importance to further reveal the biosorption behavior of the biomass under the multi-metal- component environment, as often occurred in the industrial effluents. This study started from batch-mode operations to investigate the competitive biosorption and ion exchange behaviors when two or three of Pb, Cu, and Cd ions were simultaneously present. The research then switched to the design of continuous biosorption processes, which applied hollow-fiber membrane reactors for the regeneration of the biomass, as well as for the recovery of the trapped metal ions. The batch biosorption results showed that metal adsorption capacity of the biomass decreased in the order of Cu > Pb > Cd. Evidence also showed that the adsorption sites of Pb and Cd were probably included in Cu biding sites, whereas Pb and Cd adsorption sites may be partially overlapped. When Pb, Cu, and Cd co-existed, the biomass exhibited the highest affinity to Pb, while adsorption of Cd was the least favorable. The ability to replace adsorbed metal ions from the cell surface was in the order of Pb > Cu > Cd. It is thus not surprising to observe the highest initial adsorption rate for Pb, followed by Cu, and then Cd. The results obtained from continuous hollow fiber systems showed that the removal efficiency was clearly Pb > Cu > Cd, which appeared to be consistent with batch biosorption results. In the hollow-fiber processes, the efficiency of Cu and Cd removal can be appreciably enhanced with a multi-column operation, and different adsorbed metal ions may be recovered individually with appropriate operation strategies. This study also made an attempt to modify traditional Langmuir isotherm to describe the experimental data resulted from multi-component adsorption. It is found that Model II and Model III exhibited better description of the experimental results than the original Langmuir model did. The dynamic adsorption models (Model A and B) were also developed for continuous hollow-fiber biosorption processes. Model A showed excellent predictions for the results of single-metal processes. However, the derivation of Model A may become extremely complex, and required tedious numerical manipulations, when it was arranged to describe multi-component systems. In contrast, Model B introduced the concept of mass transfer to simplify the trouble-causing dq/dt term in Model A, and thus can be easily utilized to predict the results from continuous multi-metal biosorption processes.