Membranas e organelas constituem estruturas presentes nas células dos organismos. Estas estruturas representam interfaces entre eletrólitos. Uma tentativa de descrever, interpretar e compreender a distribuição iônica nas vizinhanças destas estruturas é feita neste trabalho com a análise de resultados de experimentos obtidos na investigação de alguns sistemas: 1) Sistemas constituídos por micelas de SDS. Medidas do pH nas vizinhanças de superfícies das micelas por sondas derivadas do ácido salicílico mostra variações do pH em termos da concentração de SDS e da concentração de sal adicionado. O objetivo dos experimentos é inferir o comportamento do pH nas vizinhanças de membranas biológicas que, por dissociação de alguns fosfolipídios, podem apresentar segmentos da membrana com carga na superfície. 2) A natureza \"zwitteriônica\" das membranas biológicas motivou o estudo da \"ligação iônica\" em micelas \"zwitteriônicas\", imersas em soluções com eletrólito, em concentrações variadas de sais de Cl- e Br- com os cátions monovalentes, Li+, Na+, K+, Rb+, Cs+ e tetrametil amônio (TMA+) e bivalentes Mg2+ e Ca2+. Os experimentos consistiram em determinar a concentração de haletos próximos a micela. A técnica de captura química mostra que há um grau de seletividade que não é determinado apenas pela carga iônica. 3) Resultados preliminares do grau de dissociação no interior de vesiculas de, cloreto de dimetildioctadecil amônio, DODAC, indicam que 8% dos monômeros estão dissociados em vesículas com o diâmetro médio em torno de 150 e 300 nm. As leis fundamentais usadas para compreender os resultados estão aliadas a hipótese de que os sistemas estudados estão em equilibrio termodinâmico, que a interação eletrostática é predominante e ao potencial eletrostático é conferido o papel do potencial da força média que atua nos íons. A simplificação adicional consistindo em admitir que os íons se comportam como cargas puntiformes no que se refere à interação eletrostática conduz o modelo teórico à equação de Poisson-Boltzmann que, linearizada, resulta na equação de Debye-Hückel. Hipóteses adicionais se fazem necessárias para formular o modelo como um problema matemático com condições de contorno. Para cada situação as hipóteses adicionais são discutidas. Sistemas hipotéticos são analizados com o intuito de comparar os resultados provenientes da equação de Poisson-Boltzmann e da equação de Debye-Hückel. A análise teórica dos sistemas conduz a resultados em acordo com os valores medidos. Entre as conclusões obtidas, neste trabalho, são mencionados: 1- As sondas derivadas do ácido salicílico mantêm os grupos dissociáveis próximos a superfície, a distância é da ordem de 0,1 nm, mesmo para sondas que apresentam cadeia longa entre o grupo nitrogênio e o grupo dissociável. 2- A especificidade iônica é bem descrita utilizando, além da carga elétrica, a massa do íon. Os íons na superfície de uma micela zwitteriônica têm liberdade translacional e portanto superfícies zwitteriônicas em solução de eletrólito apresentam condutividade elétrica na superfície. 3- As concentrações iônicas no interior de vesículas são uniformes em praticamente toda a região interna, apresentando variações apenas nas vizinhanças da superfície interna carregada eletricamente. / Membranes and organelles are structures present in biological systems. Such structures are interfaces between electrolytes. Addressing to the description, interpretation and comprehension of the ionic distribution around the structures an attempt is done is this work analyzing experimental results from the investigation of the following systems: 1) SDS micelles. \"pH\" measurements in the micellar surface neighborhood using salicylic acid probes show the pH values dependence with the SDS and added salt concentrations. The experiments aimed to infer the pH behavior in biological membranes where same phospholipids may dissociate and portions of the surface can acquire electrical charges. 2) The zwitterionic nature of biological membranes leads to the investigation of ion binding in zwitterionic micelles in electrolyte solutions with varied concentrations of Cl- or Br<SUP- salts with the cations Li+, Na+, K+, Rb+, Cs+ e tetramethylammonium (TMA+) and the bivalent cations Mg2+ e Ca2+. Halide concentration in the micellar vicinity was measured. Chemical trapping method shows there is a selectivity degree that does not depend only on the ionic charge. 3) Preliminary results in the determination of the inner dissociation degree of dioctadecyldimethylammonium chloride vesicles, DODAC, show that about 8% of the vesicle constituent monomers are dissociated in vesicles with 150 and 300 nm mean diameter. The theoretical description is based upon the thermodynamics equilibrium hypothesis about the systems and that the electrostatic interaction is the stronger interaction and also it is attributed to the mean electrostatic potential the role of the mean force potential acting on the ionic species. A further simplification in considering the ions as point charges with respect to the electrostatic interactions leads the model to the Poisson-Boltzmann equation and under linearization results in the Debye-Hückel alternative description. Additional hypothesis are necessary in order to have the model as a mathematical problem with boundary conditions and are discussed for each system. Hypothetical systems are analysed aiming the comparison between Poisson-Boltzmann and Debye- Hückel descriptions. Some conclusions derived in the analysis are: 1- The salicylic acid probes have the dissociable groups always near (~0,1nm) the micellar surface, even to the probes that have a long chain between the nitrogen group and the dissociable group. 2- In a zwitterionic micelle the ions on the surface have translational freedom and this is way the zwitterionic membranes in electrolyte solutions are conducting surfaces. 3- The ionic concentrations in the vesicle interior have uniformly value almost everywhere showing variations only in the vicinity of the electrically charged interior surface. The theoretical study of the three systems considered gives results in accord with experimental data.

Oily wastewater produced from petroleum and petrochemical refining processes is one of the gravest environmental threats. Oil waste ending up in sewers and dumps each year is equal to 25 times the amount of crude oil spilled in the Exxon Valdez accident (1989). Oil/Water separation covers a broad spectrum of industrial process operations. There are many techniques employed depending on each situation. The byproduct of water recovery from oily wastewater is a sludge rich in oil, surfactants and particles (oily sludge). The oily sludge still contains significant amounts of waters, which need to be recovered prior to its disposal. The use of polyelectrolytes for the flocculation of the emulsified oil and its separation from the aqueous phase is usually one of the steps of the wastewater as well as oily sludge treatment process. The efficiency of polyelectrolytes as floculants is quite often evaluated via trial and error and the appropriate polymer is selected according to the case. Even in scientific investigations it is rather common to use industrial oily sludge samples. The industrial oily sludge is characterized and treated by polyelectrolytes. Nevertheless industrial oily sludge is quite complicated and variable to be approximated by a model. For the systematic study of polyelectrolytes efficiency a stable, realistic and well-defined oily sludge model is necessary. In the present work an oily sludge model was successfully developed and characterized. The model consists on water, oil (kerosene), surfactant (sodium dodecyl sulphate, SDS) and clay particles (Blauton). The emulsifying efficiency of the surfactant and the clay were studied independently. The interactions between the surfactant and the clay including adsorption of the former on the later and cation exchange reactions were investigated. The four components were finally combined to form a series of emulsions varying the relative amounts of the emulsifiers for the highest stability to be encountered. Having concluded on the composition of the oily sludge model the efficiency of various polyelectrolytes was evaluated. Commercial natural (chitosans), synthetic (PolyDADMACs) polyelectrolytes and oilbreaks as well as lab-scale semi-synthetic polymers (modified chitosans) were tested. The flocculation efficiency was determined based on the amount and quality of water that was recovered as well as on the floc stability, size and sedimentation speed. The recovered water was characterized according to the environmental protection agency (EPA). The analysis included measurements on: total organic carbon (TOC), chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total suspended solids (TSS) and pH. Selection of the appropriate flocculant also depends on the type of flocs formed in combination to the treatment following the flocculation. When filtration or centrifugation is used as a post-flocculation process the appropriate polymers are those that form large and porous flocs, as the case of the modified chitosans AG95 and AG97. Clarification devices on the other hand require dense flocs as these produced by the use of PolyDADMACs, commercial chitosans, oilbreaks and modified chitosans GA35, GA41 and AG79. Regarding the water quality, some of the polymers used that have low values of COD, TOC and BOD5, may not need the secondary treatment (biological) prior to discharge, such as P187K (PolyDADMAC) and GA41 (modified chitosan). The others require a biological treatment for the regulation limits to be reached. The pH values of modified chitosans (except of AG97), lab-scale PolyDADMACs and an oilbreak (OCAA) are all in range of the regulation limits. The applicability of biopolymers as flocculants for oil sludge dewatering is a relatively new field of investigation. As a consequence of the growing demand for environmentally friendly technologies as well as renewable resources the interest on natural flocculants has increased. The aminopolysaccharide chitosan and its modified derivatives have outstanding properties such as biocompability, biodegradability, hydrophilicity, adsorption, flocculating ability and antibacterial properties. These natural polymers derived from the sea-food industry waste products would be very useful as residue oil adsorbents in any oily wastewater and can be among the most promising candidates as a replacement of the synthetic flocculants. / Ölhaltiges Abwasser, das bei Erdöl- und petrolchemischen Raffinierungsprozessen entsteht, ist eine der größten Umweltgefahren. Dieses Altöl landet jedes Jahr in der Kanalisation und in Deponien. Es handelt sich dabei um die 25-fache Menge an Rohöl, die beim Unfall der Exxon Valdez (1989) ausgeflossen ist. Die Öl/Wasser-Trennung überspannt ein breites Spektrum industrieller Prozesse. Es gibt viele Techniken, die abhängig von jeder Situation eingesetzt werden. Das Nebenprodukt bei der Abtrennung von Wasser aus ölhaltigen Abwässern ist ein Schlamm (Ölschlamm), der reich an Öl, Tensiden und Partikeln ist. Der Ölschlamm enthält noch bedeutende Mengen an Wasser, die vor ihrer Entsorgung verwertet werden müssen. Die Verwendung von Polyelektrolyten zur Ausflockung des emulgierten Öls und seine Trennung von der wässrigen Phase ist in der Regel einer der Schritte zur Behandlung von Abwässern sowie ölhaltigen Schlämmen. Die Effizienz von Polyelektrolyten als Flockungsmittel wird ganz häufig über Versuch und Fehler bewertet, und das passende Polymer wird entsprechend dem jeweiligen Fall ausgewählt. Sogar in wissenschaftlichen Untersuchungen ist es eher üblich, industrielle Ölschlamm-Proben zu verwenden. Der industrielle Ölschlamm wird charakterisiert und mit Polyelektrolyten behandelt. Dennoch ist der industrielle Ölschlamm ziemlich kompliziert und variabel und muss durch ein Modell angenähert werden. Für die systematische Untersuchung der Effizienz von Polyelektrolyten als Flockungsmittel ist ein stabiles, realistisches und klar definiertes Ölschlamm-Modell notwendig. In der vorliegenden Arbeit wurde ein Ölschlamm-Modell erfolgreich entwickelt und charakterisiert. Das Modell besteht aus Wasser, Öl (Kerosin), Tensid (Natriumdodecylsulfat, SDS) und Tonteilchen (Blauton). Die Emulgiereffizienz des Tensids und des Tons wurden unabhängig voneinander untersucht. Die Wechselwirkungen zwischen dem Tensid und dem Ton, die sowohl die Adsorption des Ersteren auf dem Letzteren einschließen als auch einen Kationenaustausch, wurden untersucht. Die vier Komponenten des Ölschlamm-Modells wurden schließlich kombiniert und es wurde eine Reihe von Emulsionen hergestellt, bei denen die relativen Mengen der Emulsionsmittel verändert wurden, um eine möglichst hohe Stabilität zu erreichen. Nachdem ein geeignetes Ölschlamm-Modell zur Verfügung stand, wurde die Effizienz der verschiedenen Polyelektrolyte als Flockungsmittel bewertet. Kommerzielle natürliche (Chitosane), synthetische (PolyDADMACs) Polyelektrolyte und Oilbreaks sowie Labor-semi-synthetische Polymere (modifizierte Chitosane) wurden getestet. Die Flockungseffizienz wurde sowohl basierend auf der Menge und Qualität des Wassers, das zurückgewonnen wurde, als auch bezogen auf die Flockenstabilität, die Flockengröße und die Sedimentationsgeschwindigkeit bestimmt. Das zurückgewonnene Wasser wurde entsprechend der Vorschriften der Behörde für Umweltschutz (EPA) charakterisiert. Die Analysen enthielten die Bestimmung des gesamten organischen Kohlenstoffs (TOC), des chemischen Sauerstoffbedarf (CSB), des biochemischen Sauerstoffbedarfs (BSB5), des Gesamtgehalts an suspendierten Partikeln (TSS) und die Bestimmung des pH. Die Auswahl geeigneter Flockungsmittel hängt auch von der Art der gebildeten Flocken, in Kombination mit der Behandlung, die den Flockungsprozess folgt, ab. Wenn als Postflockungsprozess Filtration oder Zentrifugation folgen, sollten Polymere verwendet werden, die große und poröse Flöckchen bilden, wie im Fall der modifizierten Chitosane AG95 und AG97. Andererseits verlangen Geräte zur Klärung von Abwässern dichte Flocken, wie solche, die beim Einsatz von PolyDADMACs, kommerziellen Chitosanen, Oilbreaks und den modifizierten Chitosanen GA35, GA41 und AG79 entstehen. In Bezug auf die Wasserqualität erhält man mit einigen der verwendeten Polymere so niedrige Werte von CSB, TOC und BSB5, dass wie im Falle von P187K (PolyDADMAC) und GA41 (modifiziertes Chitosan) keine biologische Sekundärbehandlung notwendig ist. Im Falle der anderen Polymere ist eine biologische Behandlung nötig, um die vorgeschriebenen Grenzen zu erreichen. Die pH-Werte der modifizierten Chitosane (außer der AG97), der im Labor hergestellten PolyDADMACs und des Oilbreak OCAA sind alle in Bereich der vorgeschriebenen Grenzen. Die Anwendbarkeit von Biopolymeren als Flockungsmittel für die Ölschlammentwässerung ist ein relativ neuer Forschungsbereich. Als Folge der wachsenden Nachfrage nach umweltfreundlichen Technologien sowie erneuerbarer Ressourcen hat das Interesse an natürlichen Flockungsmitteln zugenommen. Das Aminopolysaccharidchitosan und dessen modifizierte Produkte haben hervorragende Eigenschaften wie Biokompatibilität, Biodegradierbarkeit, Hydrophilie, Adsorption, die Fähigkeit zur Flockung und antibakterielle Eigenschaften. Diese natürlichen Polymere, die aus Meeresfrüchte-Industrieabfallprodukten gewonnen werden, sollten als Restöl-Adsorbentien bei der Aufarbeitung jedes ölhaltigen Abwassers sehr nützlich sein und können zu den vielversprechendsten Kandidaten als Ersatz der synthetischen Flockungsmittel werden.

Hepatit-B är en leversjukdom som orsakas av hepatit-B-virus (HBV) vilket är en kapslad DNA-virus. Kapsidprotein (Cp) har stor betydelse i virusets livscykel exempelvis DNA-replikation, interaktion med värdceller och andra virala glykoproteiner. HBV, som många andra virus, tar sig in i cellen genom att binda till cellreceptorer. Transferrinreceptor är en välkänd receptor som mögliggör virus inträde i cellen genom att binda till virusproteiner, intraktionen sker i apikala domänen i TfR. Båda Cp149, kapsidsammansättnings domänen i Cp, och apikala domänen i TfR är betydelsefulla ändamål för utveckling av antivirala läkemedel. Syftet med arbetet var att klona och uttrycka olika varianter av ett nytt modifierat Cp149, där Cp149 har modifierats med AP01 (lösliga formen av apikala dömanen),  och analysera intraktioner mellan proteinerna och viralt glykoprotein, MGP1. Modifierade proteingener klonades i plasmid (pET-11a) med hjälp av rekombinant DNA-teknik och användning av restriktionsenzymer NdeI och BamHI. Agarosgelelektrofores och DNA-sekvensering användes för att  kontrollera förekomst av eftersökta DNA-sekvenser. Nya plasmider fördes över till bakterieceller, Escherichia coli, och  proteinutrycket inducerades i bakteriecellerna genom kemiskbehandling. Framrenade proteiner från respektive provlösning analyserades med Sodium dodecyl sulphate polyakrylamid gel electrophoresis (SDS-PAGE) och proteinernas funktion undersöktes med flödescytometri genom att besämma bindningsförmågan till MGP1, som uttrycktes på jästceller, i närvaro av TfR. Rekombinant plasmid innehållande proteingen kodande Cp149 för varianter A-D samt F lyckades att framställas. Resultatet från SDS-PAGE påvisade inga tydlyga protein-band och flödescytometri resultatet var svårt att bedömma, troligen då ytterliggare proteinupprening behövdes för att isolera kapsidproteinerna. Syftet med arbetet har erhållits delvis och fortsatt undersökningar på nya proteiner förslås. / Hepatitis B is one av the major worldwide health problems that is caused by enveloped DNA virus, Hepatitis B virus (HBV). HBV’s capsid protein (Cp) has an important role in the virus life cycle, för example DNA replication, intraction with host cells, and other viral glycoproteins. HBV, like many other viruses, enters the cells by binding to cell receptors. Transferrin receptor (TfR) is a well-known receptor that enables virus entry into the cell by binding to viral proteins. The interaction takes place in the apical domain of TfR. Both Cp149, the capsid’s composition domain of Cp, and the soluble form of the apical domain, AP01, from TfR are important builing parts to be explored as starting building blocks for the development of antiviral therapeutics. Modification of Cp149 with AP01 is an interesting combination to produce new protein-based drugs to prevent viral infections. The aim of this project was to clone and express six different variants of a AP01 modified Cp149 protein as a starting points to analyze interactions between the proteins and Machupo virus glykoprotein 1 (MGP1). All target DNA templates and plasmids (pET-11a) were digested with restriction enzymes, NdeI and BamHI, and ligated by T4 DNA ligase. Agarose gel electrophoresis and DNA sequencing were used as validation methods to confirm the presence of desired and corrected DNA sequences, respectively, during gene cloning. DNA transformation and induction of Escherichia coli cells was used to express the desired proteins. The purified proteins were validated for their binding ability to MGP1, expressed on yeast cells by flow cytometry in a competition assay with TfR. Recombinant plasmid including the expected DNA sequence encoding Cp149 for variants A-D and F was successfully produced. There was no clear detection of protein bands on Sodium dodecyl sulphate polyakrylamid gel electrophoresis (SDS-PAGE) gel and flow cytometry results were difficult to interpret due to insufficient protein purification during ammonium sulphate percipitation. The purpose of the project has been obtained partially and more studies have to be carried out to produce pure proteins that can be used for further analysis.

Proteiner spelar en avgörande roll i människokroppen och det är därför viktigt att inta tillräckligt med essentiella aminosyror genom kosten. Tidigare har animaliska källor varit kända för att vara rika på dessa aminosyror, men nu förtiden räcker det inte för att tillfredsställa den globala behov. Dessutom väcker den animaliska proteiner allvarliga frågor om klimatförändringar och etik. Ärtor innehåller en essentiell profil av aminosyror och har många andra fördelar, såsom tillgänglighet, kostnadseffektivitet och förmåga att växa i låga temperaturer. Tidigare studier har visat att regelbunden intag av ärtprotein kan minska risken för hjärt-kärlsjukdomar och diabetes. Studier visade att Naturliga djupa eutektiska lösningsmedel (NADES) kan lösa upp proteiner utan att denaturera de, vilket är ett problem med traditionella lösningsmedel som kan påverka proteinstrukturer. Dessutom är NADES icke-toxiska och biologiskt nedbrytbara lösningar, vilket gör dem mer hållbara och miljövänliga än vanliga vätskor som används vid proteinextraktion. Syftet med studien var att använda NADES för att utveckla en ny metod för att extrahera proteiner från gula ärtor och jämföra denna med etablerade metoder. Dessutom skulle skillnader i proteinutbyte och strukturella förändringar uppskattas genom användning av Size Exclusion Chromatography (SEC) och Sodium Dodecyl Sulfate PolyAcrylamide Gel Elektrofores SDS-PAGE. Tre varianter av NADES framställdes från kolinklorid, citronsyra och olika vattenhalter. NADES 20% användes för extraktion, eftersom det har visat sig vara en lämplig metod för detta ändamål. Resultaten visade att extraktion med NADES är mer komplicerad än referensmetoderna för att proteinerna utfölls vid olika steg under extraktion process. SEC-kromatogram visade proteindenaturering där en tydlig topp erhölls vid senare elueringsvolym. SDS-PAGE analys genomfördes för att identifiera toppar men inge resultat kunde erhålla på grund av låg proteinkoncentration. Från ett optimistiskt perspektiv kan de denaturerade proteinerna fortfarande användas inom livsmedelsindustrin eller NADES kan användas som en pre-extraktionsmetod för att avlägsna föroreningar innan den verkliga extraktionsprocessen påbörjas. Det skulle vara användbart för framtida studier att prova att extrahera med en lägre vattenhalt i NADES eller med en annan typ av NADES. / Protein plays a crucial role in the human body, making it essential to consume sufficient amounts of essential amino acids through diet. Traditionally, animal sources have been known to be rich in these amino acids, but this is not sufficient to meet global demand. Additionally, this raises serious questions about climate change and ethics. Peas have been found to contain an essential profile of amino acids and have many other advantages, such as availability, cost-effectiveness, and the ability to grow in low temperatures. Previous studies have shown that regular consumption of pea protein can reduce the risk of cardiovascular disease and diabetes. Studies have shown that Natural Deep Eutectic Solvents (NADES) can dissolve proteins without denaturing them, which is a problem with traditional solvents that can affect protein structures. In addition, NADES are non-toxic and biodegradable solutions, making them more sustainable and environmentally friendly than common liquids used in protein extraction. The aim of the study was to use NADES to develop a new protein extraction method from yellow peas and compare this with established methods. In addition, differences in protein yield and structural changes were estimated using Size Exclusion Chromatography (SEC) and Sodium Dodecyl Sulfate PolyAcrylamide Gel Elektrofores SDS-PAGE. Three variants of NADES were prepared from choline chloride, citric acid, and different water contents. NADES 20% was used for extraction as it has been found to be a suitable method for this purpose. The results showed that extraction with NADES is more complicated than the reference methods because the proteins precipitated at different stages during the extraction process. SEC chromatogram showed protein denaturation where a clear peak was obtained at later elution volumes. SDS-PAGE analysis was performed to identify peaks, but no results could be obtained due to low protein concentration. From an optimistic perspective, the denatured proteins can still be used in the food industry, or NADES can be used as a pre-extraction method to remove impurities before the actual extraction process begins. It would be useful for future studies to try extracting with a lower water content in NADES or with a different type of NADES.

TRIM21 is a cytosolic ubiquitin ligase and an antibody receptor that providesa last line of defense against invading pathogens. By utilizing the diversity ofantibody repertoire to identify pathogens, TRIM21 serves as a link betweenintrinsic cellular defense and adaptive immunity. A variety of diseases havebeen linked to mutations of the TRIM family, including cancer, inflammatorydiseases, and autoimmune diseases. In this project, TRIM21 was producedand purified from Escherichia coli, (E.coli). Protein characterization wasperformed with SDS-PAGE, size exclusion chromatography and cryo-electronmicroscopy (cryo-EM). Previously TRIM21 has been shown to form a dimerwhen produced in SF9. Results from size exclusion chromatography show thatTRIM21 form a larger complex when expressed in E.coli. Cryo-EM resultsshow that the complex structure is more globular than previously thought.Purified TRIM21 was bound to the antibody IC100. SDS-PAGE and sizeexclusion chromatography results show much lower affinity to antibodies thanexpected. / TRIM21 är en cytosolisk ubiquitinligas- och antikroppsreceptor som ger ensista försvarslinje mot invaderande virus. Genom att använda mångfalden avantikroppsrepertoar för att identifiera patogener, fungerar TRIM21 som enlänk mellan inre cellulärt försvar och adaptiv immunitet. En mängd olikasjukdomar har kopplats till mutationer i TRIM-familjen, inklusive cancer,inflammatoriska sjukdomar och autoimmuna sjukdomar. I detta projekt produceradesoch renades TRIM21 från Escherichia coli, (E.coli). Proteinkarakteriseringutfördes med SDS-PAGE, gelfiltreringskromatografi och kryo-elektronmikroskopi(cryo-EM). Tidigare har TRIM21 visat sig bilda en dimer när den producerasi SF9. Resultat från gelfiltrering visar att TRIM21 bildar ett större komplexnär det uttrycks i E.coli. Cryo-EM-resultat visar att den komplexa strukturenär mer klotformig än man tidigare trott. Renad TRIM21 bands till antikroppenIC100. SDS-PAGE och gel-filtrerings resultat visar mycket lägre affinitet tillantikroppar än förväntat.

No description available.

Winter rye produces ice-modifying antifreeze proteins upon cold treatment. Two of these antifreeze proteins are members of the large, highly conserved, ??-1,3-endoglucanase family. This project was designed to identify glucanase genes that are expressed during cold acclimation, wounding, pathogen infection, drought or treatment with the phytohormones ethylene and MeJa. Additionally, a more detailed proteomic analysis was to be carried out to evaluate the glucanase content of the apoplast of cold-acclimated (CA) winter rye. Results of 2D SDS-PAGE analysis revealed that non-acclimated whole leaf protein extracts contain at least two ??-1,3-endoglucanses while CA whole leaf protein extracts contain at least three ??-1,3-endoglucanses. Subsequent 2D SDS-PAGE analysis was conducted on the apoplast extracts of NA and CA winter rye plants revealed the limitations of standard 1D SDS-PAGE. The 2-dimensional gel analysis revealed that there is a minimum of 25 proteins within the apoplast of CA winter rye, including at least 5 ??-1,3-endoglucanases. Genome walking was used to isolate cold-responsive glucanase genes. The five genes isolated were designated scGlu6, scGlu9, scGlu10, scGlu11 and scGlu12. The cis-element pattern within the promoter of each gene was evaluated using online databases of documented plant cis elements. As expected, all of the promoters contained elements associated with cold, biotic and abiotic stresses, light regulation, and development. The expression patterns predicted by the cis elements in each promoter were compared to the mRNA abundance produced by each gene as detected by semi-quantitative reverse transcriptase PCR. In most cases, the abundance of transcripts arising from each gene loosely corresponded to the expression pattern predicted by the cis elements the corresponding promoter. Transcripts of scGlu9, 10 and 11 were present in cold-treated tissues and are candidates for ??-1,3-endoglucanases with antifreeze activity. The results presented in this thesis provide additional insight into the apoplast proteome of CA winter rye plants as well as the complexity of the signals controlling the proteins that reside there. Although there are still a number of unresolved questions, this research opens new directions for future studies in the cold acclimation process in winter rye and specifically for the contribution of ?? -1,3-endoglucanses.

The aim of this thesis work was to investigate theadsorption of surfactants to different nonpolar interfaces.Particularly, the effects of the polar group and the nature ofthe hydrophobic interface were elucidated. The interfacialbehavior of the liquid-vapor interface was investigated bymeans of surface tension measurements. Here the effect of thepolar group and the hydrocarbon chain length was investigatedin a systematic manner. It was found that the shorter of thetwo chains examined, decyl, generated a larger surface pressurecontribution than the longer, dodecyl. Furthermore, the sugarbased surfactants behaved differently as compared to theethylene oxide based ones. The former could be modelled byassuming a hard disc behavior of the head group while thelatter displayed polymeric behavior. The influence of saltconcentration on the surface tension behavior of an ionicsurfactant, sodium dodecyl sulphate, was investigated. Theresult could be rationalized by employing the Gouy- Chapmanmodel to the polar region. Furthermore, mixtures of two sugarbased surfactants were investigated by surface tensionmeasurements and the adsorbed amount of the two components atthe interface atdifferent concentrations and fractions in thebulk were obtained by applying the Gibbs surface tensionequation. It was found that the molecule with the smaller headgroup adsorbed preferentially, and more so as the totalsurfactant concentration was increased. These findings could beexplained by considering the interactions generated by thedifferent head groups. The adsorption of sugar surfactants toan isolated hydrophobic surface was studied by means of wettingmeasurements and the behavior was similar to that at theliquid-vapor interface. Wetting isotherms were measured on twodifferent hydrophobic surfaces where the covalently attachedhydrophobic layers were in a crystalline and fluid state,respectively. The wetting results revealed that the sugarsurfactants anchored in the fluid hydrophobic layer. This had asignificant influence on the force profile. For example, at thecrystalline surface the surfactant monolayers were easilyremoved as the surface came into contact at relatively lowapplied loads. This was not the case when the hydrophobic layerwas in a fluid state. Here a significant fraction of thesurfactants remained between the surfaces. Disjoining pressureisotherms were measured using a sugar based surfactant thatwere thoroughly purified and compared to the as receivedsample. Even the purified sample showed a double-layer forcealthough lower as compared to the as received, one. Asignificant difference in foam stability was also observed. / <p>NR 20140805</p>

Introduction: Cellular membrane proteins, such as the cytochrome P450 enzyme superfamily (P450), have important roles in the physiology of the cell. P450s are important in metabolising endogenous molecules, as well as metabolising xenobiotic substances for detoxification and excretion. P450s are also implicated in cancer as they can act to 'negatively' de-activate or 'positively' activate cancer therapeutics. Identifying specific P450s that are highly up-regulated at the tumour site could be used to predict drug response and formulate targeted cancer therapy to help diminish systemic side-effects. Methods: Previous enrichment strategies have been unable to isolate the full complement of the P450 superfamily. To develop enrichment procedures for the P450s, a proteomic strategy was developed so that compounds could be screened for their effectiveness as general P450 probes. A standardised work-flow was created, encompassing affinity chromatography, protein concentration/desalting, followed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and high performance liquid chromatography-mass spectrometry (HPLC-MS). A ketoconazole analogue and a 2-EN analogue, with known P450 inhibition, were immobilised on a solid support for comparison to immobilised histamine. Co-factor removal, competitive elution and DTT cleavage of disulfide bonds of probes were utilised to elute bound proteins. Results/Discussion: Inhibitor-beads bound a large range of proteins, including P450's, of which some were eluted by co-factor removal, some by competitive elution. Specificity of binding was improved by optimising buffer conditions and solid supports, however non-specific binding was not totally eradicated. All human P450s from spiked samples and 18 P450s from more complex mouse liver samples were recovered using one or more ligands.

Contexte : Les systèmes à logiciels prépondérants sont de plus en plus interopérables formant des alliances nommées « Systèmes-des-Systèmes » (SdS). Les applications des SdS peuvent aller des systèmes de gestion du trafic jusqu’aux systèmes de gestion de crises. Étant donné que les SdS supportent souvent des domaines critiques, ils doivent être fiables en traitant les disfonctionnements ou les défauts et en évitant les défaillances qui pourraient causer des dégâts et pertes importantes aux utilisateurs.Problème : Ajuster les opérations d’un SdS dépend d’une spécification précise et une attestation rigoureuse de sa consistance opérationnelle. Cependant, en plus des limitations des langages pour capturer conjointement la structure et le comportement des SdS, les prédictions de la consistance opérationnelle des SdS reposent sur leurs systèmes constitutifs qui ne sont pas totalement connus au moment de la conception. Par conséquent, les SdS ont été développés et déployés sans évaluation de leurs opérations, puisque les langages actuels ne supportent pas ce type de précision lors de l’évaluation. Objectif : Cette thèse fournit des solutions théoriques et pratiques basées sur un langage formel de description d’architectures pour supporter une évaluation précoce des opérations du SdS par rapport à la structure et le comportement du SdS à travers les simulations. Contributions : Les contributions essentielles de ce projet comprennent (i) une approche de transformation des modèles pour produire automatiquement des modèles de simulation à partir des descriptions des architectures logicielles du SdS, combinant la description structurelle et comportementale du SdS dans la même solution, (ii) une méthode d’évaluation de l’architecture logicielle du SdS pour la prédiction des opérations du SdS tout en considérant les changements inhérents qui peuvent se produire, (iii) la modélisation de l’environnement et la génération automatique des générateurs de stimulus pour soutenir la simulation des SdS, livrant des données pour nourrir tel simulation, et (iv) une méthode pour la synchronisation automatique entre l’architecture descriptive d’exécution (qui change à l’exécution par suite de l’architecture dynamique) et son architecture prescriptive d’origine basée sur des mécanismes de découverte et de récupération de modèles et une transformation de modèle à l'envers.Évaluation : Nous avons conduit des cas d’études pour évaluer nos approches en utilisant le SdS de surveillance des inondations et le SdS d’espace.Résultats : Notre approche montre une précision importante pour (i) produire des simulations des architectures logicielles des SdS sans failles et complètement opérationnelles, (ii) supporte une évaluation et une prédiction fiable des opérations du SdS à la phase de conception, (iii) génère de manière automatique des générateurs de stimuli pour soutenir et nourrir l’exécution de la simulation et (iv) maintien la synchronisation entre les versions descriptives et prescriptives de l’architecture du SdS.Conclusion : Nous avons conclu que les approches proposées font évoluer l’état de l’art de l’évaluation des architectures logicielles des SdS en offrant des solutions pour prédire l’efficacité des opérations du SdS pour maintenir une opération continue malgré les changements architecturaux, fournissant plus de confidence aux utilisateurs qui reposent dans l’avenir sur les services du SdS. / Context: Software-intensive systems have been increasingly interoperated forming alliances termed as “Systems-of-Systems” (SoS). SoS comprises a collection of systems joined to achieve a set of missions that none of the systems can individually accomplish. Each constituent system keeps its own management, goals, and resources while coordinating within the SoS and adapting to meet SoS goals. Applications of SoS range from traffic control to emergency response and crisis management. As SoS often support critical domains, such systems must be trustworthy by dealing with malfunction or defects and avoiding failures that could cause extensive damage and losses to the users.Problem: Correct SoS operations depend on a precise specification of the SoS structure and a rigorous attestation of its behaviors. However, besides limitations on languages to jointly capture SoS structure and behavior, predictions on the SoS emergent behaviors rely on constituent systems not totally known at design-time. Therefore, SoS have been developed and deployed without evaluating their operation, since current languages do not support such precision in evaluation.Objectives: This PhD project provides solutions founded on a formal architectural description language to support an early evaluation of SoS behaviors regarding its inherent SoS structure and dynamics through simulations.Contribution: The main contributions of this project comprise (i) a model transformation approach for automatically producing simulation models from SoS software architecture descriptions, combining SoS structure and behavior description in a same solution, (ii) a SoS software architecture evaluation method for SoS operation prediction considering the inherent changes that can occur, (iii) environment modeling and automatic generation of stimuli generators to sustain the SoS simulation, delivering data to feed such simulation, and (iv) a method for the automatic synchronization between the runtime descriptive architecture (changed at runtime due to dynamic architecture) and its original prescriptive architecture based on model discovery and recovery mechanisms and a backward model transformation.Evaluation: We conducted case studies to assess our approaches using Flood Monitoring SoS and Space SoS.Results: Our approaches show a high accuracy to (i) produce fault-free and operational simulations for SoS software architectures, (ii) support a reliable evaluation and prediction of SoS operation at design-time, (iii) automatically generate stimuli generators to sustain and feed the simulation execution, and (iv) maintain the synchronization between descriptive and prescriptive versions of the SoS architecture.Conclusions: We concluded that the proposed approaches advance the state of the art in SoS software architecture evaluation by offering solutions to predict the SoS operations effectiveness to maintain a continuous operation despite architectural changes, providing more trust for users that in the future shall rely on SoS services.