Neste trabalho utilizaram-se dois sistemas para pesquisar alguns dos fatores que alteram a velocidade de reações em sistemas micelares. A reação de transferência de acila de S-octanoil-β-mercaptoetilamina (OMA) é catalisada 4,6 vezes por micelas de brometo de hexadeciltrimetilamônio (CTAB) e levemente inibida por Brij-35. A reação de transferência de acila de S para N da acetil-β-mercaptoetilamina (AMA) não é afetada por CTAB, porém é inibida cerca de 100 vezes por dodecil sulfato de sódio (SDS). A reação de OMA também é fortemente inibida por SDS (1.700 vezes). Estes efeitos foram atribuídos a uma alteração do pK do grupo amino e à diminuição da liberdade conformacional da molécula de substrato na fase micelar. O CTAB aumenta a velocidade de tiólise de acetato de p-nitrofenila por tiofenóis substituídos aproximadamente 50 vezes. A constante de velocidade calculada na fase micelar (k2m) é idêntica a obtida em fase aquosa (k2w) para tiofenol, p-metoxitiofenol e p-metiltiofenol. k2m é 40% menor do que k2w na reação com p-clorotiofenol. A aceleração observada em presença de CTAB pode ser atribuída, exclusivamente, à concentração de substrato na fase micelar. / Two systems were used in order to investigate some of the factors that modify the reaction rate in micelles. The rate of S to N acyl transfer of S-octanoyl-β- mercaptoethylamine (OMA) is enhanced by hexadecyl trimethylammonium bromide (CTAB) micelles by 4.6 fold and slightly inhibited by the non ionic detergent Brij-35. The rate of S to N transfer of S-acetyl-β-mercaptoethylamine (AMA) is unaffected by CTAB or Brij-35. Micelles of a negative detergent, sodium dodecyl sulfate inhibit the rate of S to N transfer of AMA by 100 fold, the inhibition in the case of OMA is 1.7 x 103 fold. An increase in the apparent pK of the ammonium ion and a decrease in the conformational mobility of OMA is proposed to account for the observed results. CTAB increases the rate of thiolysis of p-nitrophenyl acetate by substituted thiophenols by approximately 50 fold. The calculated rate constant in the micellar phase (k2m) is identical to that in the aqueous phase (k2w) for thiophenol, p-methoxithiophenol and p-metilthiophenol. k2m is 40% less than k2w in the case of p-clorothiophenol. The observed rate acceleration can be attributed, exclusively, to substrate concentration in the micellar phase.

El uso de estereotipos de género en la publicidad peruana es una realidad consecuente al machismo presente en este país, siendo un claro ejemplo la marcada presencia de la ama de casa en la publicidad televisiva de detergentes. No obstante, la marca Bolívar muestra en una de sus campañas publicitarias a dos protagonistas en un contexto distinto al hogar. En la presente investigación se busca analizar la manera en que influye la imagen de la mujer peruana moderna representada en la campaña publicitaria “Lúcete con Bolívar”, para generar brand awareness en las estudiantes de la Universidad Peruana de Ciencias Aplicadas. Para resolver esta interrogante, se plantea la metodología de investigación cualitativa mediante el enfoque del estudio de caso. Por ende, se analiza la campaña “lúcete con Bolívar” teniendo en cuenta la imagen de las protagonistas como principal objeto de investigación. De acuerdo al contexto peruano actual, resulta relevante entender cómo influye la imagen de las protagonistas de la campaña, y si esta tiene un impacto positivo en el brand awareness de las participantes del estudio. / The use of gender stereotypes in Peruvian advertising is a reality consistent with the machismo present in this country, a clear example being the marked presence of the housewife in television advertising of detergents. However, the Bolívar brand shows in one of its advertising campaigns two protagonists in a context other than home. This research seeks to analyze the way in which the image of the modern Peruvian woman represented in the advertising campaign "Lúcete con Bolívar" influences, to generate brand awareness in the students of the Peruvian University of Applied Sciences. To resolve this question, the qualitative research methodology is proposed through the case study approach. Therefore, the “shine with Bolívar” campaign is analyzed taking into account the image of the protagonists as the main object of investigation. According to the current Peruvian context, it is relevant to understand how the image of the protagonists of the campaign influences, and if it has a positive impact on the brand awareness of the study participants. / Trabajo de investigación

The research in this thesis considers novel innovative developments in established industrial processes that involve the use of recyclable polymeric particles as a partial replacement for aqueous media and chemicals. The application of the technology typically leads to water savings of over 80% and chemical savings of over 25%. These industrial processes may be characterised in that are considered inefficient and wasteful but nevertheless are considered economically vital. These diverse industries including laundry cleaning, leather manufacturing, textile garment processing, effluent treatment and metal beverage can manufacture. The outcomes of this research have made significant contributions to industrial best practice in such industries. In terms of academic research, the knowledge created in this thesis provides the basis for the application of CFD-DEM modelling to understand complex multi-phase and multi-component systems. In particular, the thesis advocates the application of the Free Surface Lattice Boltzmann Method for creating highly accurate simulations of multi-phase flow. In addition, the thesis offers opportunities for further research in novel plasma micro-reactors and their applications in diverse fields such as chemical synthesis, chemical engineering and biotechnology. The nature of the research is multi-disciplinary, and involved investigations across several fields including applied mathematics, biochemistry, chemistry, physics, and engineering. The projects also involved scale up from laboratory, pilot plant and full commercial scale production trials. Primary objectives were investigated through a series of six published patents. The three patents relating to the development of novel leather and textile processes were solely conceived and executed by the author. The patent related to the development of the plasma micro-reactor for ozone synthesis was conceived and executed jointly by the author and Professor Will Zimmerman (Sheffield University). The two patents related to the development of a novel metal cleaning and treatment process was conceived and executed jointly by the author and Dr. Robert Bird (Xeros Technology Group Limited).

Les systèmes modèles (vésicules géantes unilamellaires) représentent un outil indispensable pour étudier la formation, la stabilité, la dynamique et les fonctions des rafts dans les membranes biologiques. L'originalité de notre étude réside : i) dans la visualisation du bourgeonnement et de la fission induits par des agents biologiques (sPLA2 ou Lyso PC) et ii) dans la visualisation directe de la solubilisation d'une membrane modèle de type Ld/Lo ainsi que le bourgeonnement et la fission des domaines Lo traitée avec des détergents (Triton X-100, Brij 98). Ces expériences appuient l'idée que l'isolement de DRM à partir des membranes cellulaires n'est probablement pas un artefact. Nous avons décrit un mécanisme possible pour l'expulsion d'une vésicule en phase Lo déclenché par des molécules d'asymétrie stérique positive. Enfin, les VGU hétérogènes peuvent présenter un modèle assez proche des phénomènes observés sur les membranes biologiques.

This master thesis studies environmental effects of a detergents' compactation project. The theoretical part describes negative environmental effects of detergents' use and foreign initiatives having successfully led to decrease of these effects. The analytical part evaluates the information campaign focused on customer behavior and detergent dosage through a market survey. Lower detergent consumption is a prerequisite of a decreased negative environmental impact. Market data showing real detergent consumption are compared to expected development. Results of the market survey and the market data analysis show that a change in consumer behavior was not sufficient; and therefore, the compactation project was not successful.

Modelling and evaluating the aquatic fate of detergents - Abstract Within this thesis an environmental assessment and evaluation method for analysing aquatic ecotoxicological impacts of household laundry is developed. The methodology allows comparative assessments of different product alternatives, washing habits, and wastewater treatment techniques in order to identify their relevance with respect to waterborne discharges. Elements from both analytical tools Life Cycle Assessment (LCA) and Environmental Risk Assessment of chemicals (ERA) are combined in this methodology. The core consists of the Geography-referenced Regional Exposure Assessment Tool for European Rivers (GREAT-ER), which calculates concentrations of `down-the-drain' chemicals in surface waters due to point releases. In order to simulate the aquatic fate of detergents, a new GREAT-ER emission model is developed, called GREAT-ER product mode, which calculates calculates concentration increases of detergent ingredients in surface waters based on product formulations and assumptions concerning washing habits. Two evaluation methods, the Critical Length (CL) and the Product Risk Ratio (PRRx), are defined for evaluating the results. CL is the sum of mean concentration increases, divided by substance-specific no effect concentrations (NECs), over all river stretches and all ingredients weighted by the lengths of the stretches. PRRx is the (percentual) number of river stretches in a region, in which the x-percentiles of the predicted concentration increases of at least one ingredient exceed a substance-specific NEC. The emission model requires input data that can be derived from the functional unit of an LCA, which allows an assessment of other impact categories by using any existing LCA method. The methodology is applied to a case study which is based on scenarios given in the comprehensive product assessment `Washing and washing agents' (`Produktlinienanalyse', PLA). In order to apply the GREAT-ER product mode, the Rur river basin in Western North-Rhine Westphalia is chosen as study area. The catchment integration includes the development of a simple hydrological model that combines a nonlinear regression analysis with a local refinement procedure. The quality of the integration of the Rur catchment data is analysed by a comparison of monitoring data and predicted concentrations of detergent and cleaning agent ingredients using actual consumption data of the two years 1993 and 2000. The product mode results show that use habits have a larger influence on the results than product formulations. However, the largest influence is caused by varying wastewater treatment techniques. Boron and the surfactants are the most relevant detergent ingredients. Furthermore, using different detergents for white and coloured laundry lowers the predicted emissions significantly. Based on this methodology, sustainable development indicators (SDIs) for describing the aquatic aspects of household laundry are defined. CL is proposed as pressure indicator and PRRx as state indicator for describing aquatic aspects of the sustainability of household laundry in a region. Different regions can be compared by normalising the CL by the region's population and expressing the PRRx as a percentage of stretches in a region. Annually evaluating regional CLs and PRRxs allows the assessment whether a region is moving towards a more sustainable state. Concluding, the new method analyses and evaluates the environmental fate of detergents discharged after use via the wastewater pathway. It provides information not obtainable by other existing methods, which has been made possible due to the focussing on a specific application, for which the method is developed. Its application in the context of sustainable development offers a means to evaluate environmental implications of this important human activity.

The nuclear lamina protein, lamin A is produced by proteolytic cleavage of a 74 kDa precursor protein, prelamin A. The conversion of this precursor to mature lamin A is mediated by a specific endoprotease, prelamin A endoprotease. Subnuclear fractionation indicates that the prelamin A endoprotease is localized at the nuclear membrane. The enzyme appears to be an integral membrane protein, as it can only be removed from the nuclear envelope with detergent. It is effectively solubilized by the detergent n-octyl-beta-D-glucopyranoside and can be partially-purified (approximately 1200-fold) by size exclusion and cation exchange (Mono S) chromatography. Prelamin A endoprotease from HeLa cells was eluted from Mono S with 0.3 M sodium chloride as a single peak of activity. SDS-PAGE analysis of this prelamin A endoprotease preparation shows that it contains one major polypeptide at 65 kDa and smaller amounts of a second 68 kDa polypeptide. Inhibition of the enzyme activity in this preparation by specific serine protease inhibitors is consistent with the enzyme being a serine protease.

Les liposomes sont des structures sphériques formés par l'auto-assemblage de molécules amphiphiles sous forme d'une bicouche. Cette bicouche sépare le volume intérieur du liposome du milieu extérieur, de la même manière que les membranes cellulaires. Les liposomes sont donc des modèles de membranes cellulaires et sont formulés pour étudier les processus biologiques qui font intervenir la membrane (transport de molécules à travers la membrane, effets des charges en surface, interactions entre la matrice lipidique et d'autres molécules, etc.). Parce qu'ils peuvent encapsuler une solution aqueuse en leur volume intérieur, ils sont aussi utilisés aujourd'hui comme nanovecteurs de principes actifs. Nous avons formulé des liposomes non-phospholipidiques riches en stérol que nous avons appelés stérosomes. Ces stérosomes sont composés d'environ 30 % d'amphiphiles monoalkylés et d'environ 70 % de stérols (cholestérol, Chol, et/ou sulfate de cholestérol, Schol). Quand certaines conditions sont respectées, ces mélanges sont capables de former une phase liquide ordonnée (Lo) pour donner, par extrusion, des vésicules unilamellaires. Certaines de ces nouvelles formulations ont été fonctionnalisées de manière à libérer leur contenu en réponse à un stimulus externe. En incorporant des acides gras dérivés de l’acide palmitique possédant différents pKa, nous avons pu contrôler le pH auquel la libération débute. Un modèle mathématique a été proposé afin de cerner les paramètres régissant leur comportement de libération. En incorporant un amphiphile sensible à la lumière (un dérivé de l’azobenzène), les liposomes formés semblent répondre à une radiation lumineuse. Pour ce système, il serait probablement nécessaire de tracer le diagramme de phase du mélange afin de contrôler la photo-libération de l’agent encapsulé. Nous avons aussi formulé des liposomes contenant un amphiphile cationique (le chlorure de cétylpyridinium). En tant que nanovecteurs, ces stérosomes montrent un potentiel intéressant pour la libération passive ou contrôlée de principes actifs. Pour ces systèmes, nous avons développé un modèle pour déterminer l’orientation des différentes molécules dans la bicouche. La formation de ces nouveaux systèmes a aussi apporté de nouvelles connaissances dans le domaine des interactions détergents-lipides. Aux nombreux effets du cholestérol (Chol) sur les systèmes biologiques, il faut ajouter maintenant que les stérols sont aussi capables de forcer les amphiphiles monoalkylés à former des bicouches. Cette nouvelle propriété peut avoir des répercussions sur notre compréhension du fonctionnement des systèmes biologiques. Enfin, les amphiphiles monoalkylés peuvent interagir avec la membrane et avoir des répercussions importantes sur son fonctionnement. Par exemple, l'effet antibactérien de détergents est supposé être dû à leur insertion dans la membrane. Cette insertion est régie par l'affinité existant entre le détergent et cette dernière. Dans ce cadre, nous avons voulu développer une nouvelle méthode permettant d'étudier ces affinités. Nous avons choisi la spectroscopie Raman exaltée de surface (SERS) pour sa sensibilité. Les hypothèses permettant de déterminer cette constante d’affinité se basent sur l’incapacité du détergent à exalter le signal SERS lorsque le détergent est inséré dans la membrane. Les résultats ont été comparés à ceux obtenus par titration calorimétrique isotherme (ITC). Les résultats ont montré des différences. Ces différences ont été discutées. / Liposomes are spherical structures formed by the self-assembly of amphiphilic molecules to form bilayers. The bilayer separates the interior volume of the liposome from the external milieu, as do cellular membranes. Liposomes are cellular membrane models and are used to study biological processes that occur in relation with the membrane (molecular transport across the membrane, surface charge effects, interactions between the lipid matrix and other molecules, etc.). Because they can encapsulate an aqueous solution in their interior volume, they are also used as nanovectors of active agents. We have formulated non-phospholipid liposomes enriched in sterol that we have named sterosomes. These sterosomes are composed of approximately 30 % of monoalkylated amphiphiles and around 70 % of sterols (cholesterol, Chol, and/or cholesterol sulfate, Schol). Under certain conditions, these mixtures are able to form a liquid ordered phase (Lo) and unilamellar vesicles by extrusion. Some of these new formulations were functionalized in order to release their content in response to an external stimulus. By incorporating fatty acids (palmitic acid derivatives) with different pKas, we were able to control the pH at which the release starts. A mathematical model has been proposed in order to get insights on the parameters that control their release behavior. By incorporating a light-sensitive amphiphile (an azobezene derivative), liposomes seem to respond to an irradiation. For this system, it is probably necessary to plot the phase diagram of the mixture in order to control the photo-release of the encapsulated agent. We also have formulated liposomes containing a cationic amphiphile (cetylpyridinium chloride). As nanovectors, these sterosomes show an interesting potential for passive or active agent controlled release. For these systems, a model has been developed in order to study the orientation of the different molecules in the bilayer. The formation of these new formulations has also contributed to new knowledge in the detergent-lipid interaction field. Added to the numerous known effects of cholesterol (Chol) on biological systems, we must now add that sterols are also able to force monoalkylated amphiphiles to form bilayers. This new property can have an impact on our comprehension of biological system functioning. Finally, monoalkykated amphiphiles can interact with the membrane and have a negative impact on its functioning. For example, the antibactericidal effect of detergents is supposed to be due to their insertion in the membrane. This insertion is related to the affinity between the detergent and the membrane. Within this field, we wanted to develop a new method to investigate detergent-membrane affinities. We chose surface enhanced Raman Spectroscopy (SERS) due to its sensitivity. Hypotheses allowing the determination of affinity constants are based on the incapability of the detergent to enhance the SERS signal when the detergent is inserted in the membrane. Results were compared to those obtanined bi isothermal titration calorimetry (ITC). Differences were found and are discussed.

Les liposomes sont des structures sphériques formés par l'auto-assemblage de molécules amphiphiles sous forme d'une bicouche. Cette bicouche sépare le volume intérieur du liposome du milieu extérieur, de la même manière que les membranes cellulaires. Les liposomes sont donc des modèles de membranes cellulaires et sont formulés pour étudier les processus biologiques qui font intervenir la membrane (transport de molécules à travers la membrane, effets des charges en surface, interactions entre la matrice lipidique et d'autres molécules, etc.). Parce qu'ils peuvent encapsuler une solution aqueuse en leur volume intérieur, ils sont aussi utilisés aujourd'hui comme nanovecteurs de principes actifs. Nous avons formulé des liposomes non-phospholipidiques riches en stérol que nous avons appelés stérosomes. Ces stérosomes sont composés d'environ 30 % d'amphiphiles monoalkylés et d'environ 70 % de stérols (cholestérol, Chol, et/ou sulfate de cholestérol, Schol). Quand certaines conditions sont respectées, ces mélanges sont capables de former une phase liquide ordonnée (Lo) pour donner, par extrusion, des vésicules unilamellaires. Certaines de ces nouvelles formulations ont été fonctionnalisées de manière à libérer leur contenu en réponse à un stimulus externe. En incorporant des acides gras dérivés de l’acide palmitique possédant différents pKa, nous avons pu contrôler le pH auquel la libération débute. Un modèle mathématique a été proposé afin de cerner les paramètres régissant leur comportement de libération. En incorporant un amphiphile sensible à la lumière (un dérivé de l’azobenzène), les liposomes formés semblent répondre à une radiation lumineuse. Pour ce système, il serait probablement nécessaire de tracer le diagramme de phase du mélange afin de contrôler la photo-libération de l’agent encapsulé. Nous avons aussi formulé des liposomes contenant un amphiphile cationique (le chlorure de cétylpyridinium). En tant que nanovecteurs, ces stérosomes montrent un potentiel intéressant pour la libération passive ou contrôlée de principes actifs. Pour ces systèmes, nous avons développé un modèle pour déterminer l’orientation des différentes molécules dans la bicouche. La formation de ces nouveaux systèmes a aussi apporté de nouvelles connaissances dans le domaine des interactions détergents-lipides. Aux nombreux effets du cholestérol (Chol) sur les systèmes biologiques, il faut ajouter maintenant que les stérols sont aussi capables de forcer les amphiphiles monoalkylés à former des bicouches. Cette nouvelle propriété peut avoir des répercussions sur notre compréhension du fonctionnement des systèmes biologiques. Enfin, les amphiphiles monoalkylés peuvent interagir avec la membrane et avoir des répercussions importantes sur son fonctionnement. Par exemple, l'effet antibactérien de détergents est supposé être dû à leur insertion dans la membrane. Cette insertion est régie par l'affinité existant entre le détergent et cette dernière. Dans ce cadre, nous avons voulu développer une nouvelle méthode permettant d'étudier ces affinités. Nous avons choisi la spectroscopie Raman exaltée de surface (SERS) pour sa sensibilité. Les hypothèses permettant de déterminer cette constante d’affinité se basent sur l’incapacité du détergent à exalter le signal SERS lorsque le détergent est inséré dans la membrane. Les résultats ont été comparés à ceux obtenus par titration calorimétrique isotherme (ITC). Les résultats ont montré des différences. Ces différences ont été discutées. / Liposomes are spherical structures formed by the self-assembly of amphiphilic molecules to form bilayers. The bilayer separates the interior volume of the liposome from the external milieu, as do cellular membranes. Liposomes are cellular membrane models and are used to study biological processes that occur in relation with the membrane (molecular transport across the membrane, surface charge effects, interactions between the lipid matrix and other molecules, etc.). Because they can encapsulate an aqueous solution in their interior volume, they are also used as nanovectors of active agents. We have formulated non-phospholipid liposomes enriched in sterol that we have named sterosomes. These sterosomes are composed of approximately 30 % of monoalkylated amphiphiles and around 70 % of sterols (cholesterol, Chol, and/or cholesterol sulfate, Schol). Under certain conditions, these mixtures are able to form a liquid ordered phase (Lo) and unilamellar vesicles by extrusion. Some of these new formulations were functionalized in order to release their content in response to an external stimulus. By incorporating fatty acids (palmitic acid derivatives) with different pKas, we were able to control the pH at which the release starts. A mathematical model has been proposed in order to get insights on the parameters that control their release behavior. By incorporating a light-sensitive amphiphile (an azobezene derivative), liposomes seem to respond to an irradiation. For this system, it is probably necessary to plot the phase diagram of the mixture in order to control the photo-release of the encapsulated agent. We also have formulated liposomes containing a cationic amphiphile (cetylpyridinium chloride). As nanovectors, these sterosomes show an interesting potential for passive or active agent controlled release. For these systems, a model has been developed in order to study the orientation of the different molecules in the bilayer. The formation of these new formulations has also contributed to new knowledge in the detergent-lipid interaction field. Added to the numerous known effects of cholesterol (Chol) on biological systems, we must now add that sterols are also able to force monoalkylated amphiphiles to form bilayers. This new property can have an impact on our comprehension of biological system functioning. Finally, monoalkykated amphiphiles can interact with the membrane and have a negative impact on its functioning. For example, the antibactericidal effect of detergents is supposed to be due to their insertion in the membrane. This insertion is related to the affinity between the detergent and the membrane. Within this field, we wanted to develop a new method to investigate detergent-membrane affinities. We chose surface enhanced Raman Spectroscopy (SERS) due to its sensitivity. Hypotheses allowing the determination of affinity constants are based on the incapability of the detergent to enhance the SERS signal when the detergent is inserted in the membrane. Results were compared to those obtanined bi isothermal titration calorimetry (ITC). Differences were found and are discussed.

Alors que 30% du génome code pour des protéines membranaires, moins de 3% des structures protéiques dans la Protein Data Bank correspondent à ces protéines. En raison de leur nature hydrophobe, les protéines membranaires sont en effet très difficiles à produire dans des systèmes d'expression classique en cellules, notamment en bactéries. L'étude structurale des protéines membranaires du virus de l'hépatite C (VHC) sous forme entière et native a donc été pendant longtemps entravée. Le VHC est un virus à ARN positif dont le complexe de réplication est basé sur un réarrangement spécifique des membranes induit par l'action concertée de plusieurs protéines non structurales du virus dont NS2, NS4B et NS5A. La structure tridimensionnelle et le rôle de ces protéines dans la réplication virale sont encore mal connus. Pour surmonter les limitations qui empêchent leurs études structurales et fonctionnelles, un système d'expression acellulaire à base d'extrait de germe de blé a été développé avec succès, permettant la production des protéines NS2, NS4B et NS5A entières directement sous une forme solubilisée en présence de détergent. Ces protéines membranaires sont produites et purifiées par chromatographie d'affinité dans des quantités de l'ordre du milligramme. Des analyses par filtration sur gel indiquent que les échantillons obtenus sont homogènes. De plus, des analyses structurales par dichroïsme circulaire montrent que les protéines produites dans ce système sont bien repliées. Leur reconstitution dans des lipides est en cours d'optimisation. Le but ultime est en effet de déterminer leur structure par RMN du solide dans un environnement lipidique mimant l'environnement natif / While 30% of the genome encodes for membrane proteins, less than 3% of protein structures in the Protein Data Bank correspond to such proteins. Due to their hydrophobic nature, membrane proteins are indeed notoriously difficult to express in classical cell-based protein expression systems. The structural study of the membrane proteins of hepatitis C virus (HCV) in their full-length and native form has therefore been for long time hampered. HCV is a positive-strand RNA virus building its replication complex on a specific membrane rearrangement (membranous web), which serves as a scaffold for the HCV replicase, and is induced by the concerted action of several HCV non-structural proteins including NS2, NS4B and NSSA. The knowledge of the three- dimensional structure of these proteins and their role in virus replication is still limited. To overcome the limitations that prevent the structural and functional studies of these proteins, a wheat germ cell-free protein expression system has been developed. A production protocol was designed which allows us to directly obtain membrane proteins in a soluble form by adding detergent during the in vitro protein synthesis. A large number of mainly viral proteins were successfully expressed, and full protocols were developed for the full-length NS2, NS4B and NSSA proteins. These membrane proteins were produced and purified by affinity chromatography using a Strep-tag II in the milligram range. These protein samples are homogenous, as shown by gel filtration analysis. Moreover, structural analyses by circular dichroism showed that the proteins produced in the wheat germ cell-free system are well folded. Reconstitution of these proteins in lipids is currently under optimization. The ultimate goal is to determine their structure by solid-state NMR in a native-like membrane lipids environment