32 research outputs found

    Designing an artificial Golgi reactor for cell-free glycosylation

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    Glycosylation of therapeutically relevant proteins such as monoclonal antibodies (mAbs), is critical as it can offer increased drug efficiency, efficacy and half-life. Therefore, the production of modern biotherapeutics focuses on controlling the protein glycosylation profile using various methods. Currently, the dominating method is the traditional cell-line engineering of host cells such as mammalian cells. The main goal is to produce mAbs with a human-like glycosylation pattern. However, this approach often struggles due to high sensitivity to the fermentation environment making it difficult to scale up and control. The latter can lead to structural heterogeneity amongst the products which can be immunogenic. In addition to the in vivo methods, there are many in vitro techniques such as chemoselective or enzymatic glycosylation. However, they are often limited by the difficult implementation and, as before, product heterogeneity due to lack of control over the enzymatic reactions. In line with the need to control glycosylation in the production of therapeutic proteins, we propose an artificial Golgi reactor for in vitro glycosylation. By expressing selected glycosyltransferases and immobilizing them on solid supports we can achieve sequential enzymatic reactions required for protein glycosylation. The spatial separation will allow strict control over the reaction conditions while addressing enzyme promiscuity. Both should enhance product quality. Furthermore, we aim to perform a single-step glycosyltransferases purification/immobilization. Thanks to that, as well as the modularity of our design, the proposed system would be more sustainable and easily tailored for each application, thus producing any desired glycoform to homogeneity. A detailed mathematical approach to design and optimisation of the proposed artificial Golgi reactor focusing on mAb therapeutics has been published [1]. The authors report an optimisation of the reactor design and operational parameters that directs the whole process towards the desired glycan structure. In this research project, we have achieved expression and in vivo biotinylation of Nicotiana Tabacum GnTI (NtGnTI) and human GalT in E. coli. The biotinylated enzymes were successfully bound to streptavidin beads and used for artificial glycan synthesis. NtGnTI and GalT reacted in a sequential fashion to produce the glycan GalGlcNAcMan5GlcNAc2, as confirmed with MALDI/TOF MS analysis. In the future, we aim in extending the pathway of immobilized enzymes thus demonstrating the importance of this novel platform for in vitro glycosylation. References: [1] Klymenko, O. V., Shah, N., Kontoravdi, C., Royle, K. E. & Polizzi, K. M. Designing an Artificial Golgi reactor to achieve targeted glycosylation of monoclonal antibodies. AIChE J. 62, 2959–2973 (2016)

    Low-cost and user-friendly biosensor to test the integrity of mRNA molecules suitable for field applications

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    The use of mRNA in biotechnology has expanded with novel applications such as vaccines and therapeutic mRNA delivery recently demonstrated. For mRNA to be used in patients, quality control assays will need to be routinely established. Currently, there is a gap between the highly sophisticated RNA integrity tests available and broader application of mRNA-based products by non-specialist users, e.g. in mass vaccination campaigns. Therefore, the aim of this work was to develop a low-cost biosensor able to test the integrity of a mRNA molecule with low technological requirements and easy end-user application. The biosensor is based on a bi-functional fusion protein, composed by the λN peptide that recognizes its cognate aptamer encoded on the 5’ end of the RNA under study and β-lactamase, which is able to produce a colorimetric response through a simple test. We propose two different mechanisms for signal processing adapted to two levels of technological sophistication, one based on spectrophotometric measurements and other on visual inspection. We show that the proposed λN-βLac chimeric protein specifically targets its cognate RNA aptamer, boxB, using both gel shift and biolayer interferometry assays. More importantly, the results presented confirm the biosensor performs reliably, with a wide dynamic range and a proportional response at different percentages of full-length RNA, even when gene-sized mRNAs were used. Thus, the features of the proposed biosensor would allow to end-users of products such as mRNA vaccines to test the integrity of the product before its application in a low-cost fashion, enabling a more reliable application of these products

    Rhamnolipid and surfactin production from olive oil mill waste as sole carbon source

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    Olive mill waste (OMW) creates a major environmental problem due to the difficulty of further waste processing. In this work we present an approach to give OMW added value by using it for the production of biosurfactants. Two bacterial species, Pseudomonas aeruginosa and Bacillus subtilis, were grown with OMW as the sole carbon source. Glycerol and waste frying oil were used as comparative carbon sources. B. subtilis produced surfactin (a lipopeptide) at a maximum concentration of 3.12 mg/L with 2% w/v of OMW in the medium, dropping to 0.57 mg/L with 10% w/v of OMW. In contrast, P. aeruginosa produced 8.78 mg/L of rhamnolipid with 2% w/v OMW increasing to 191.46 mg/L with 10% w/v OMW. The use of solvent-extracted OMW reduced the biosurfactant production by 70.8 % and 88.3 % for B. subtilis and P. aeruginosa respectively. These results confirm that OMW is a potential substrate for biosurfactant production

    Spent coffee grounds as feedstock for the production of biosurfactants and the improved recovery of melanoidins

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    Spent coffee grounds (SCG) are wastes generated in high amounts worldwide. Their composition makes them a promising feedstock for biotechnological processes. Here we show that the production of the biosurfactant surfactin by submerged culture of a Bacillus subtilis strain growing on SCG is possible, reaching concentrations up to 8.8 mg/L when using SCG at 8.3 g/L in the medium. In addition, we report a synergy between the production of surfactin and the recovery of melanoidins, an added-value compound already present in SCG. More specifically, the concentration of melanoidins in the culture medium increased between 2.1 and 2.5 times thanks to the presence of the B. subtilis in the culture. Furthermore, we have observed a strong interaction between surfactin and melanoidin aggregates through dynamic light scattering measurements, and that both of them can be co-purified with an acid precipitation. We have also characterized the interfacial and antioxidant properties of the cell-free supernatant and surfactin extract, as well as the distribution of the congeners of the biosurfactant. Altogether, this work describes a promising approach to obtain biosurfactants and antioxidant molecules in a single operation, which can be used to design several new formulations of interest for bioremediation, amendment of soils, food and cosmetics

    Immobilized enzyme cascade for targeted glycosylation

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    Glycosylation is a critical post-translational protein modification that affects folding, half-life and functionality. Glycosylation is a non-templated and heterogeneous process because of the promiscuity of the enzymes involved. We describe a platform for sequential glycosylation reactions for tailored sugar structures (SUGAR-TARGET) that allows bespoke, controlled N-linked glycosylation in vitro enabled by immobilized enzymes produced with a one-step immobilization/purification method. We reconstruct a reaction cascade mimicking a glycosylation pathway where promiscuity naturally exists to humanize a range of proteins derived from different cellular systems, yielding near-homogeneous glycoforms. Immobilized β-1,4-galactosyltransferase is used to enhance the galactosylation profile of three IgGs, yielding 80.2–96.3% terminal galactosylation. Enzyme recycling is demonstrated for a reaction time greater than 80 h. The platform is easy to implement, modular and reusable and can therefore produce homogeneous glycan structures derived from various hosts for functional and clinical evaluation.UKRI Engineering and Physical Sciences Research Council (EP/N509486/1)UKRI Engineering and Physical Sciences Research Council (EP/K038648/1, EP/H04986X/1 and EP/K038648/1)UK Research and Innovation ‘Global Challenges Research Fund’ BB/P02789X/1)UK Biotechnology and Biological Sciences Research Counci

    Egg sac construction by folding dead leaves in Pozonia nigroventris and Micrathena sp. (Araneae: Araneidae)

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    Published descriptions of egg sac construction behavior in araneids are scarce. We describe egg sac construction and oviposition in one individual of the poorly known araneid Pozonia nigroventris (Bryant 1936) and two individuals of Micrathena sp. These spiders folded dead leaves to protect their eggs. All individuals pulled up and hung a dead leaf above the forest floor, oviposited on the leaf, and then folded the leaf around the egg sac. They then deposited the enclosed egg sac in the leaf litter below. The use of dead leaves in this way probably evolved convergently, since these genera are only distantly related.Smithsonian Tropical Research Institute, Panama, USAUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí

    5to. Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad. Memoria académica

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    El V Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad, CITIS 2019, realizado del 6 al 8 de febrero de 2019 y organizado por la Universidad Politécnica Salesiana, ofreció a la comunidad académica nacional e internacional una plataforma de comunicación unificada, dirigida a cubrir los problemas teóricos y prácticos de mayor impacto en la sociedad moderna desde la ingeniería. En esta edición, dedicada a los 25 años de vida de la UPS, los ejes temáticos estuvieron relacionados con la aplicación de la ciencia, el desarrollo tecnológico y la innovación en cinco pilares fundamentales de nuestra sociedad: la industria, la movilidad, la sostenibilidad ambiental, la información y las telecomunicaciones. El comité científico estuvo conformado formado por 48 investigadores procedentes de diez países: España, Reino Unido, Italia, Bélgica, México, Venezuela, Colombia, Brasil, Estados Unidos y Ecuador. Fueron recibidas un centenar de contribuciones, de las cuales 39 fueron aprobadas en forma de ponencias y 15 en formato poster. Estas contribuciones fueron presentadas de forma oral ante toda la comunidad académica que se dio cita en el Congreso, quienes desde el aula magna, el auditorio y la sala de usos múltiples de la Universidad Politécnica Salesiana, cumplieron respetuosamente la responsabilidad de representar a toda la sociedad en la revisión, aceptación y validación del conocimiento nuevo que fue presentado en cada exposición por los investigadores. Paralelo a las sesiones técnicas, el Congreso contó con espacios de presentación de posters científicos y cinco workshops en temáticas de vanguardia que cautivaron la atención de nuestros docentes y estudiantes. También en el marco del evento se impartieron un total de ocho conferencias magistrales en temas tan actuales como la gestión del conocimiento en la universidad-ecosistema, los retos y oportunidades de la industria 4.0, los avances de la investigación básica y aplicada en mecatrónica para el estudio de robots de nueva generación, la optimización en ingeniería con técnicas multi-objetivo, el desarrollo de las redes avanzadas en Latinoamérica y los mundos, la contaminación del aire debido al tránsito vehicular, el radón y los riesgos que representa este gas radiactivo para la salud humana, entre otros

    Effectiveness of an intervention for improving drug prescription in primary care patients with multimorbidity and polypharmacy:Study protocol of a cluster randomized clinical trial (Multi-PAP project)

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    This study was funded by the Fondo de Investigaciones Sanitarias ISCIII (Grant Numbers PI15/00276, PI15/00572, PI15/00996), REDISSEC (Project Numbers RD12/0001/0012, RD16/0001/0005), and the European Regional Development Fund ("A way to build Europe").Background: Multimorbidity is associated with negative effects both on people's health and on healthcare systems. A key problem linked to multimorbidity is polypharmacy, which in turn is associated with increased risk of partly preventable adverse effects, including mortality. The Ariadne principles describe a model of care based on a thorough assessment of diseases, treatments (and potential interactions), clinical status, context and preferences of patients with multimorbidity, with the aim of prioritizing and sharing realistic treatment goals that guide an individualized management. The aim of this study is to evaluate the effectiveness of a complex intervention that implements the Ariadne principles in a population of young-old patients with multimorbidity and polypharmacy. The intervention seeks to improve the appropriateness of prescribing in primary care (PC), as measured by the medication appropriateness index (MAI) score at 6 and 12months, as compared with usual care. Methods/Design: Design:pragmatic cluster randomized clinical trial. Unit of randomization: family physician (FP). Unit of analysis: patient. Scope: PC health centres in three autonomous communities: Aragon, Madrid, and Andalusia (Spain). Population: patients aged 65-74years with multimorbidity (≥3 chronic diseases) and polypharmacy (≥5 drugs prescribed in ≥3months). Sample size: n=400 (200 per study arm). Intervention: complex intervention based on the implementation of the Ariadne principles with two components: (1) FP training and (2) FP-patient interview. Outcomes: MAI score, health services use, quality of life (Euroqol 5D-5L), pharmacotherapy and adherence to treatment (Morisky-Green, Haynes-Sackett), and clinical and socio-demographic variables. Statistical analysis: primary outcome is the difference in MAI score between T0 and T1 and corresponding 95% confidence interval. Adjustment for confounding factors will be performed by multilevel analysis. All analyses will be carried out in accordance with the intention-to-treat principle. Discussion: It is essential to provide evidence concerning interventions on PC patients with polypharmacy and multimorbidity, conducted in the context of routine clinical practice, and involving young-old patients with significant potential for preventing negative health outcomes. Trial registration: Clinicaltrials.gov, NCT02866799Publisher PDFPeer reviewe

    Outpatient Parenteral Antibiotic Treatment vs Hospitalization for Infective Endocarditis: Validation of the OPAT-GAMES Criteria

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