Immobilization of Proteins in Poly-Styrene-Divinylbenzene Matrices: Functional Properties and Applications

Supports based on poly-styrene-divinylbenzene (PSD) are commercially available since a long time ago. However, they are not commonly used as enzyme immobilization matrices. The main reason for this lies in the negative effect of the very hydrophobic surface on enzyme stability that produces the instantaneous enzyme inactivation in many instances. However, they have recently regained some impact in enzyme immobilization. They are easy to modify, and have been prepared with different modifiers. We will pay special attention to the coating of these supports with ionic liquids, which permits to have the ionic liquid phase anchored to the solid and modulate the enzyme properties without risk of losing these expensive and potentially toxic compounds. Thus, this review will present the covalent or physical immobilization of enzymes on PSD supports, submitted to different modifications. Moreover, lipases immobilized via interfacial activation on some naked PSD supports have shown some unexpected improvement in their catalytic properties, with uses in reactions like hydrolysis, esterification or transesterification.We gratefully recognize the support from the Spanish Government, CTQ2013-41507-R and CNPq (Brazil). The predoctoral fellowships for Ms. García-Galán (Spanish Government), Mr K. Hernandez (I3P-CSIC) and Mr dos Santos (CNPq, Brazil) are also recognized. ). Á. Berenguer-Murcia thanks the Spanish Ministerio de Ciencia e Innovacion for a Ramon y Cajal fellowship (RyC-2009-03813)

Lecitase ultra: A phospholipase with great potential in biocatalysis

Lecitase Ultra is a chimera produced by the fusion of the genes of the lipase from Thermomyces lanuginosus and the phospholipase A1 from Fusarium oxysporum. The enzyme was first designed for the enzymatic degumming of oils, as that problem was not fully resolved before. It is commercialized only as an enzyme solution by Novo Nordisk A/S. This review shows the main uses of this promising enzyme. Starting from the original degumming use, the enzyme has found applications in many other food modification applications, like production of structured phospholipids (e.g., derivatives of phosphatidylcholine), tuning the properties of flour, etc. Moreover, the enzyme has been used in fine chemistry (resolution of racemic mixtures), in the production of aromas and fragrances, polymers modification, etc. Some papers show the use of the enzyme in biodiesel production. Moreover, we present the different technologies applied to obtain a suitable immobilized biocatalyst, remarking the immobilization via interfacial activation and how heterofunctional acyl supports may solve some of the limitations. Immobilized enzyme physical and chemical modifications have also been presented. Finally, Lecitase Ultra has been one of the model enzymes in a new strategy to coimmobilize lipases and other less stable enzymes.We gratefully recognize the financial support from MINECO from Spanish Government (project number CTQ2017-86170-R), Colciencias, Ministerio de Educación Nacional, Ministerio de Industria, Comercio y Turismo e ICETEX, Convocatoria Ecosistema Científico – Colombia Científica. Fondo Francisco José de Caldas, Contrato RC-FP44842-212-2018, Colciencias (Colombia, project number FP 44842-076-2016), Generalitat Valenciana (PROMETEO/2018/076), FAPERGS (project number 17/2551-0000939-8), FUNCAP (project number BP3-0139-00005.01.00/18) and CONACYT (Mexico, project number CB-2016-01, 286992)

Evaluation of the bibliometric scenario of the Delphi method with Brazilian affiliations

The Delphi method is a technique used to reach consensus among specialists in an area who will be able to predict demands or analyze conjunctures about strategic themes. Within this context, the present work consisted of a bibliometric evaluation performed in the Scopus database with the aid of VOSviewer software, prioritizing journals with an affiliation of Brazilian institutions and that made use of the Delphi method for the development of their research. Data collection went through validation stages, and the results obtained showed that this tool was used in several areas of knowledge, with great emphasis on health, more specifically in Medicine, Nursing, and Public health. Together, these three areas accounted for more than 60% of publications made available

Polyethylenimine: a very useful ionic polymer in the design of immobilized enzyme biocatalysts

This review discusses the possible roles of polyethylenimine (PEI) in the design of improved immobilized biocatalysts from diverse perspectives. This includes their use to activate supports and immobilize enzymes via ion exchange, as well as to improve immobilized enzymes by coating with PEI. PEI is a polymer containing primary, secondary and tertiary amino groups, having a strong anion exchange capacity under a broad range of conditions, and the capability to chemically react with different moieties on either an enzyme or a support. Also, as a multifunctional polymer, it has been modified stepwise to introduce different functionalities into the same polymer. This polymer (in combination with other anionic ones) permits the generation of “saline” environments around enzyme molecules, improving enzyme stability in the presence of hydrophobic compounds. The use of PEI as a physical glue useful to crosslink enzyme subunits in multimeric enzymes, monomeric enzymes immobilized via physical interactions or production of enzyme multilayers will be specially emphasized as new open avenues for enzyme coimmobilization. The coimmobilization of enzymes and cofactors using PEI may become one of the future developments allowed through an adequate use of this polymer and new pathways towards the design of enzyme combi-catalysts for their use in cascade reactions. Some unexplored but suggested uses derived from the properties of PEI are also proposed in the review, like the use of the buffering power of this multifunctional polymer to avoid pH gradients inside biocatalyst particles. Thus, although PEI has been a largely popular polymer in biocatalyst design, it looks like a long and in some cases almost unexplored road lies ahead.This work was supported by grants from the Spanish Ministry of Economy and Competitiveness (MINECO) project number CTQ2013-41507-R, CNPq (process 403505/2013-5). A. B. M. thanks MINECO, Generalitat Valenciana and FEDER (CTQ2015-66080-R MINECO/FEDER and PROMETEOII/2014/010) for financial support

A INVENÇÃO DO DISCURSO VERDE NA AMAZÔNIA

O presente texto faz parte das reflexões da pesquisa:  Interfaces do discurso verde na Amazônia.  O objetivo que motivou a escrita deste artigo  é repensar e discutir os conceitos, as implicações sociológicas, antropológicas e discursivas dos termos freqüentemente usados por governos amazônicos da  tríade para o desenvolvimento  verde.  Nestes espaços  (Acre, Amazonas e Amapá)  o discurso assume conotação imprescindível, pois ele é  constitutivo  e construtor de um poder estatal ampliado. O poder é percebido nos jogos ideológicos uma vez que ‘’a materialidade ideológica só seja possível de ser apreendida a partir da materialidade lingüística’’,  (PÊCHEUX,  1988, p.116),  que aparece nas formações discursivas,  ou seja, a ideologia do discurso  aparece no dizer concreto de cada sujeito. O discurso torna-se práxis neste assujeitamento ideológico que conduz cada pessoa a acreditar que, a partir de sua livre vontade, pode se colocar, sob a forma discursiva, no lugar de uma ou outra classe social. Pois, se espera que a população local, induzida por estas políticas as legitimem, as incorporem, as defendam, as elejam como ótimas e corretas do ponto de vista das mudanças do mundo atual

The emergence of arboviruses changes the profile of viral meningitis in Salvador, Bahia: A case series

Background: Recently, different arboviruses became endemic in Brazil mostlycausing acute febrile illnesses, however, neurological manifestations have alsobeen reported. This study aimed to investigate which viruses were involved inthe meningitis etiology and the contribution of the circulating arboviruses inSalvador, Bahia, Brazil.Methods: From June 2014 to February 2016, 170 patients with suspected viralmeningitis were identified in Couto Maia Hospital, Salvador-BA, Brazil. TheirCSF samples were investigated for possible viral etiology by reversetranscription-PCR (RT-PCR) for different arboviruses: DENV, ZIKV and CHIKV;and for the EV; and by PCR for the HHV1-5 complex (HSV1-2, VZV, EBV andCMV). Also, ELISA was carried out in a subgroup of remaining samples fordetection of DENV IgM and NS1 antigen, CHIKV IgM and ZIKV IgM.Results: Thirty-seven patients were PCR or ELISA positive for at least one of thestudied viruses (overall positivity 21.8%). EV was the agent most frequentlydetected (10 cases; 27.0%), along with all four DENV serotypes (10 cases;27.0%); followed by CHIKV (6 cases; 16.2%), ZIKV (6 cases; 16.2%), and Varicellazoster virus (VZV) (1 case; 2.7%). Four cases (10.8%) presented viral co-infectiondetected: DENV1 + CHIKV, DENV1 + EV, DENV4 + ZIKV, and CHIKV + ZIKV.Arboviruses (DENV, CHIKV and ZIKV) accounted for the great majority of cases(26 cases; 70.3%) of all single and co-infections: DENV has been the mostfrequently detected arbovirus (13 cases; 35.1%). Among non-arboviralmeningitis,the most common etiology was the EV (11 cases; 29.7%).Conclusions: Arboviruses accounted for the majority of identified virusesamong patients with suspected viral meningitis. In areas where they areendemic it is crucial to increase viral surveillance and consider them in thedifferential diagnosis of meningitis.Fil: Dias, Tamiris T.. Fundación Oswaldo Cruz; BrasilFil: Tauro, Laura Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú; ArgentinaFil: Macêdo, Lara E. N.. Fundación Oswaldo Cruz; BrasilFil: Brito, Liz O.. Fundación Oswaldo Cruz; BrasilFil: Ribeiro, Victor H. O.. Fundación Oswaldo Cruz; BrasilFil: Santos, Cleiton S.. Fundación Oswaldo Cruz; BrasilFil: Jacob-Nascimento, Leile C.. Fundación Oswaldo Cruz; BrasilFil: Vilas-Boas, Letícia S.. Fundación Oswaldo Cruz; BrasilFil: Amado, Caio. Fundación Oswaldo Cruz; BrasilFil: Barbosa, Paula S.. Fundación Oswaldo Cruz; BrasilFil: Reis, Joice N.. Fundación Oswaldo Cruz; BrasilFil: Soares Campos, Gubio. Fundación Oswaldo Cruz; BrasilFil: Ribeiro, Guilherme S.. Fundación Oswaldo Cruz; BrasilFil: Siqueira, Isadora C.. Fundación Oswaldo Cruz; BrasilFil: Silva, Luciano K.. Fundación Oswaldo Cruz; BrasilFil: Reis, Mitermayer G.. Fundación Oswaldo Cruz; Brasi

Novozym 435: the “perfect” lipase immobilized biocatalyst?

Novozym 435 (N435) is a commercially available immobilized lipase produced by Novozymes. It is based on immobilization via interfacial activation of lipase B from Candida antarctica on a resin, Lewatit VP OC 1600. This resin is a macroporous support formed by poly(methyl methacrylate) crosslinked with divinylbenzene. N435 is perhaps the most widely used commercial biocatalyst in both academy and industry. Here, we review some of the success stories of N435 (in chemistry, energy and lipid manipulation), but we focus on some of the problems that the use of this biocatalyst may generate. Some of these problems are just based on the mechanism of immobilization (interfacial activation) that may facilitate enzyme desorption under certain conditions. Other problems are specific to the support: mechanical fragility, moderate hydrophilicity that permits the accumulation of hydrophilic compounds (e.g., water or glycerin) and the most critical one, support dissolution in some organic media. Finally, some solutions (N435 coating with silicone, enzyme physical or chemical crosslinking, and use of alternative supports) are proposed. However, the N435 history, even with these problems, may continue in the coming future due to its very good properties if some simpler alternative biocatalysts are not developed.We gratefully recognize the financial support from MINECO from the Spanish Government (project number CTQ2017-86170-R, Colciencias, Ministerio de Educación Nacional, Ministerio de Industria, Comercio y Turismo e ICETEX, Convocatoria Ecosistema Científico – Colombia Científica. Fondo Francisco José de Caldas, Contrato RC-FP44842-212-2018 and Colciencias (Colombia) (project number FP44842-076-2016), Generalitat Valenciana (PROMETEO/2018/076), FAPERGS (project number 17/2551-0000939-8), CONICET (R. Argentina), FUNCAP (project number BP3-0139-00005.01.00/18) and ANPCyT (PICT 2015-0932 and PICT CABBIO 4687)

甘味受容体における呈味調節物質作用モデルの構築及びその検証

学位の種別: 課程博士審査委員会委員 : (主査)東京大学准教授 三坂 巧, 東京大学教授 伏信 進矢, 東京大学特任教授 朝倉 富子, 東京大学准教授 永田 宏次, 東京大学准教授 寺田 透University of Tokyo(東京大学

Detection and Quantification of Leptospira interrogans in Hamster and Rat Kidney Samples: Immunofluorescent Imprints versus Real-time PCR

A major limitation in the clinical management and experimental research of leptospirosis is the poor performance of the available methods for the direct detection of leptospires. In this study, we compared real-time PCR (qPCR), targeting the lipL32 gene, with the immunofluorescent imprint method (IM) for the detection and quantification of leptospires in kidney samples from the rat and hamster experimental models of leptospirosis. Using a virulent strain of Leptospira interrogans serovar Copenhageni, a chronic infection was established in the rat model, which were euthanized 28 days post-infection, while the hamster model simulated an acute infection and the hamsters were euthanized eight days after inoculation. Leptospires in the kidney samples were detected using culture isolation, qPCR and the IM, and quantified using qPCR and the IM. In both the acute and chronic infection models, the correlation between quantification by qPCR and the IM was found to be positive and statistically significant (P<0.05). Therefore, this study demonstrates that the IM is a viable alternative for not only the detection but also the quantification of leptospires, particularly when the use of qPCR is not feasible