Introdução: Uma proporção significante de pacientes infectados por HIV-1 (pacientes HIV-1+) tratados com inibidores de protease (IPs) desenvolve mutações de resistência. Estudos recentes têm mostrado que células T CD8+ de pacientes HIV- 1+ reconhecem epitopos de Pol incluindo mutações selecionadas por drogas. Nenhum epitopo CD4+ da protease foi descrito na base de dados de Los Alamos. Objetivo: Considerando que a protease de HIV-1 é alvo de terapia antiretroviral e que essa pressão pode selecionar mutações, nós investigamos se mutações selecionadas por IPs afetariam o reconhecimento de epitopos da protease de HIV-1 por células T CD4+ em pacientes tratados com IPs. Nós investigamos o reconhecimento de três regiões da protease preditas de conter epitopos de células T CD4+ bem como mutações induzidas por IPs por células T CD4+ em pacientes HIV- 1+ tratados com IPs. Materiais e Métodos: Quarenta pacientes HIV-1+ tratados com IPs foram incluídos (30 em uso de Lopinavir/ritonavir, 9 em uso de Atazanavir/Ritonavir e 1 em uso exclusivo de Atazanavir). Para cada paciente determinou-se a seqüência endógena da protease de HIV-1, genotipagem viral e tipagem HLA classe II. Utilizamos o algoritmo TEPITOPE para selecionar peptídeos promíscuos, ligadores de múltiplas moléculas HLA-DR, codificando as três regiões da protease de HIV-1 cepa HXB2 (HXB2 4-23, 45-64, e 76-95) e 32 peptídeos adicionais contidos nas mesmas regiões incorporando as mutações induzidas por IPs mais freqüentes no Brasil. Os 35 peptídeos foram sintetizados. Respostas proliferativas de células T CD4+ e CD8+ aos peptídeos foram determinadas por ensaios de proliferação com diluição do corante CFSE. Ensaios de ligação a alelos HLA classe II foram realizados para confirmar a promiscuidade desses peptídeos e avaliar a habilidade de se ligarem a moléculas HLA presentes em cada paciente. Resultados: Todos os peptídeos foram reconhecidos por pelo menos um paciente e respostas proliferativas de células T CD4+ e CD8+ a pelo menos um peptídeo da protease de HIV-1 foram encontradas em 78% e 75% dos pacientes, respectivamente. A terceira região (Protease 76 95) foi a mais freqüentemente reconhecida. Ao compararmos as respostas de células T às seqüências da protease do HIV-1 endógeno, observamos que a maioria dos pacientes não foi capaz de reconhecer peptídeos idênticos às essas seqüências, porém reconheceram peptídeos variantes diferentes das mesmas regiões. Apenas sete pacientes responderam às seqüências endógenas. Verificamos que diversos peptídeos endógenos que não foram reconhecidos apresentaram ausência de ligação a alelos HLA portados por estes pacientes, sugerindo que mutações selecionadas por pressão imune tenham levado ao escape de apresentação de antígeno e evasão de resposta de linfócitos T CD4+. Alternativamente, isso poderia ser explicado pela presença de um vírus replicante distinto presente no plasma uma vez que somente foram obtidas seqüências provirais. Conclusão: Epitopos selvagens e mutantes da protease do HIV-1 reconhecidos por células T CD4+ foram identificados. Também verificamos que a maior parte dos pacientes não reconheceu as seqüências da protease endógena enquanto que reconheceram seqüências variantes. O reconhecimento de seqüências não-endógenas poderia ser hipoteticamente conseqüência de alvo de populações HIV-1 minoritárias; protease de HERV que contém regiões de similaridade com a protease do HIV-1; ou seqüências de HIV-1 presentes apenas em parceiros virêmicos. A falha de reconhecimento de seqüências endógenas seria mais provável devido ao escape imune, do que ao nível de apresentação ou reconhecimento por células T. Isso implica em uma conseqüência patofisiológica na evasão de respostas de células T contra a protease de HIV-1 e no fato de ser tradicionalmente considerada uma proteína pouco antigênica / Introduction: A significant proportion of protease inhibitor (PI)-treated HIV-1 infected (HIV-1+) patients develop resistance mutations. Recent studies have shown that CD8+ T cells from HIV-1 patients can recognize antiretroviral drug-induced mutant Pol epitopes. No HIV-1 protease CD4 epitopes are described in the Los Alamos database. Aims: Given that the protease of HIV-1 is a target of antiretroviral therapy and this pressure may lead to the selection of mutations, we investigated whether PI-induced mutations affect the recognition of HIV-1 protease epitopes by CD4 + T cells in PI-treated patients. We investigated the recognition of three protease regions predicted to harbor CD4+ T cell epitopes as well as PI-induced mutations by CD4+ T cells of PI-treated HIV-1+ patients. Methods: Forty PI-treated HIV-1+ patients were included (30 undergoing Lopinavir/ritonavir, 9 undergoing Atazanavir/ritonavir and 1 undergoing exclusively Atazanavir treatment). For each patients, the endogenous HIV-1 protease sequence, viral genotype and HLA class II typing were determined. We used the TEPITOPE algorithm to select promiscuous, multiple HLA-DR-binding peptides encoding 3 regions of HIV-1 HXB2 strain protease (HXB2 4-23, 45-64, and 76-95) and 32 additional peptides contained in the same regions, but encompassing the most frequent PI-induced mutations in Brazil. The 35 peptides were thus synthesized. Proliferative responses of CD4+ and CD8+ T cells against peptides were determined by the CFSE dilution assay. HLA class II binding assays were made to confirm the promiscuity of these peptides and evaluate their ability to bind the HLA molecules carried by each patient. Results: All tested peptides were recognized by at least one patient and proliferative responses of CD4+ and CD8+ T cells against at least one HIV-1 protease peptide were found in 78% and 75% patients, respectively. The third region (Protease 76-95) was the most frequently recognized. By comparing T-cell responses to HIV-1 endogenous protease sequences, we found that most patients failed to recognize identical peptides of those sequences, but recognized different variant peptides of the same region. Only seven patients responded to endogenous sequences. We found that several endogenous peptides that failed to be recognized showed no binding to the HLA alleles carried by that given patient, suggesting that mutations selected by immune pressure have led to escape of antigen presentation, as well as direct escape of the CD4+ T cell response. Alternatively, it could have been due to the presence of a different replicating virus in the plasma-since we only obtained proviral sequences. Conclusion: Wild-type and mutant HIV-1 protease epitopes recognized by CD4+ T cells were identified. We also found that most patients failed to recognize their endogenous protease sequences, while they recognized variant sequences. The recognition of non-endogenous sequences could hypothetically be a consequence of targeting a minor HIV-1 population; HERV protease, that contains regions of similarity with HIV-1 protease; or HIV-1 sequences present only in viremic partners. The failure to recognize endogenous sequences is most likely due to immune escape, either at the level of presentation or direct T cell recognition. This may have a pathophysiological consequence on evasion of T cell responses against protease and the fact that it has been considered traditionally a poorly antigenic HIV-1 protein.

Made available in DSpace on 2015-04-20T12:31:24Z (GMT). No. of bitstreams: 1 Raimundo Felipe da Cruz Filho.pdf: 1412659 bytes, checksum: aba20cdd1aa35484f5932ead0d0bc3e7 (MD5) Previous issue date: 2013-04-18 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The fibrinolytic proteases degrade fibrin clots and therefore play an important role in the pharmaceutical industry as chemotherapeutic agents in the treatment of cardiovascular diseases. These biocatalysts were gradually discovered from plants, insects, earthworms, snakes and microorganisms (bacteria and fungi). Cardiovascular disease has been one of the leading causes of death in the world. A major cause of heart disease is the accumulation of fibrin in the arteries, causing thrombosis. According to the World Health Organization (WHO), about 17.5 million people will die of cardiovascular disease this year, and in 2030, this amount will be 23.6 million. Given the great potential of microbial biodiversity and the growing regional Amazon applicability of enzymes in the production of drugs, this research was conducted with the objective to (1) evaluate the growth of Bacillus stearothermophilus, (2) establish growth parameters associated with production of fibrinolytic proteases in submerged fermentation and (3) assess the effect of the extractive fermentation in the separation of these enzymes. In this study techniques of extractive fermentation and solid-state fermentation were employed. By submerged fermentation the following parameters were determined: Profile of growth of Bacillus stearothermophilus and the production of protease using 100 mL of the liquid medium [(g / L) 2 g KH2PO4, (NH4)2SO4 1 g, MgSO4 7H2O 0,1 g Na2HPO4 2H2O 0,9 g, yeast extract 1 g, distilled water 1000 ml] pH 7.2 supplemented with 0.5% gelatin in an 500 mL Erlenmeyer flask. The growth of the bacteria was determined at 610 nm, once every 2 hours for 36 hours. To determine the best conditions for the production of proteases were evaluated the influence of pH, stirring and temperature, age of inoculum and substrate concentration, the influence of natural sources of carbon (tapioca, arraruta and crueira), nitrogen sources and aeration. In the recovered extract was also performed a toxicity bioassay in Artemia salina and degradation tests in vitro of the blood clot by the fibrin plate method and the artificial clot degradation in tube. In addition, the partition coefficient (K), the purification factor (PF) and recovering the enzyme were determined. The solid-state fermentation was performed using as substrate 10g of manteiguinha bean [Vigna unguiculata (L.) Walp] with 60% humidity, pH 5.0 in a 250 ml Erlenmeyer flask. In extractive fermentation the best conditions were pH 5.0, 180 rpm and 25 °C in systems using PEG 1000 (g/mol-1) to 20% (w/w) and phosphate salts 15% (w/w) with K 1.05; FP 1.00; 152.54 Y. 34 mm halo in fibrin plate and partial degradation of the clot in tube. In the solid-state fermentation, the production of protease was 8.87 (U/mL), 23 mm of translucent halo in fibrin plate with total degradation of the blood clot in 24 hours. In this study, protease produced from Bacillus stearothermophilus by extractive fermentation and semi-solid fermentation was evaluated, showing in the optimum cultivation conditions that this microorganism presents physiology for industrial application in the production of the fibrinolytic protease / As proteases fibrinolíticas degradam coágulos de fibrina, por isso têm um importante papel na indústria farmacêutica como agentes quimioterapêuticos no tratamento de doenças cardiovasculares. Estes biocatalisadores foram descobertos gradualmente a partir de plantas, insetos, anelídeos, serpentes e micro-organismos (bactérias e fungos). Doenças cardiovasculares tem sido a principal causa de morte no mundo. Uma das principais causas de doenças cardíacas é o acúmulo de fibrina nas artérias, acarretando trombose. De acordo com Organização Mundial da Saúde (OMS), cerca de 17,5 milhões de pessoas morrerão este ano de doenças cardiovasculares, e em 2030, esse montante será de 23,6 milhões. Tendo em vista o grande potencial da biodiversidade microbiana regional Amazônica e a crescente aplicabilidade de enzimas na produção de medicamentos, esta pesquisa foi realizada com o objetivo de (1) avaliar o crescimento de Bacillus stearothermophilus, (2) estabelecer os parâmetros de crescimento associado a produção de proteases fibrinolíticas por fermentação submersa e (3) verifica o efeito da fermentação extrativa na separação dessas enzimas. Neste estudo foram empregados técnicas de fermentação extrativa e fermentação semi-sólida. Por fermentação submersa foram determinados os seguintes parâmetros: Perfil do crescimento de Bacillus stearothermophilus e a produção de protease utilizando 100mL do meio líquido [(g/L) KH2PO4 2g; (NH4)2SO4 1g; MgSO4 7H2O 0,1 g; Na2HPO4 2H2O 0,9 g; Extrato de Levedura 1 g; água destilada 1000mL] pH 7,2 suplementado com gelatina 0,5%, em frasco de Erlenmeyer de 500mL. O crescimento da bactéria foi determinado a 610nm, de 2 em 2 horas, durante 36 horas. Na Determinação das melhores condições para produção de proteases foram avaliados a influência do pH; agitação, temperatura, a idade do inóculo, da concentração do substrato, a influência das fontes de naturais de carbono (tapiocas, araruta e crueira), fontes de nitrogênio e aeração. No extrato recuperado foi realizado também bioensaio de toxicidade em Artemia salina e testes de degradação in vitro do coágulo sanguíneo pelos métodos da placa de fibrina e degradação do coagulo artificial em tubo. Foi determinado também o coeficiente de partição (K), o fator de purificação (FP) e a recuperação da enzima. A fermentação semi-sólida foi realizada utilizando como substrato 10g feijão manteiginha [Vigna unguiculata (L.) Walp], com 60% umidade, pH 5,0 em frasco Erlenmeyers de 250 mL. Na fermentação extrativa as melhores condições foram: pH 5,0; 180 rpm e 25 ºC, no sistemas utilizaram PEG 1000 (g/mol-1) a 20% (p/p) e sais fosfato a 15% (p/p) com K de 1,05; FP de 1,00; Y de 152,54. Halo de 34 mm na placa de fibrina e degradação parcial do coagulo em tubo. Na fermentação semi-sólida a produção de protease foi de 8,87 (U/mL), halo translucido de 23 mm em placa de fibrina com degradação total do coagulo de sangue em 24h. No presente estudo, protease de Bacillus stearothermophilus produzido em fermentação extrativa e fermentação semi-sólida foi avaliada, demonstrando nas condições ótimas de cultivo que este micro-organismo apresenta fisiologia para aplicações industriais na produção de protease fibrinolítica

Genes de plantas que codificam inibidores de enzimas digestivas de insetos têm sido introduzidos em plantas cultivadas visando o controle de pragas. Os inibidores de proteinases estão presentes nos tecidos vegetais, principalmente nas sementes, e atuam em resposta a ataques por herbívoros e patógenos. Inibidores de serino-proteinases (IPs) dos tipos Bowman-Birk e Kunitz isolados de sementes de soja foram inseridos em variedades de cana-de-açúcar para aumentar a resistência à broca Diatraea saccharalis (Fabr.), principal praga desta cultura. Para utilização de plantas geneticamente modificadas contendo inibidores de proteinases é necessário um conhecimento profundo de sua sustentabilidade e segurança ambiental, determinando a estabilidade da característica inserida e os seus efeitos nos organismos não-alvo. O objetivo desta pesquisa foi avaliar os efeitos diretos e indiretos de inibidores de proteinases de soja em organismos não-alvos: um parasitóide larval, Cotesia flavipes (Cam.) (Hymenoptera: Braconidae); um patógeno, Metarhizium anisopliae (Mestch.) Sorokin (Deuteromycotina: Hyphomycetes); um polinizador, Apis mellifera L. (Hymenoptera: Apidae) e um decompositor, Scheloribates praeincisus (Berlese) (Acari: Oribatida: Scheloribatidae); associados à cultura da cana-de-açúcar. O consumo de Kunitz e BBI não afetou a sobrevivência de S. praeincisus. Por outro lado, a ingestão dos inibidores semi-purificados e purificados do tipo Kunitz diminuiu a duração das fases imaturas de S. praeincisus. A ingestão de folhas de cana GM expressando inibidores de proteinases (Kunitz e BBI) não afetou o tempo de desenvolvimento e a sobrevivência dos imaturos deste oribatídeo quando comparada à ingestão de suas isolinhas. Os inibidores de proteinases semi-purificados e purificados não afetaram a duração dos períodos larval e pupal, o peso e número de pupas e percentual de emergência do parasitóide C. flavipes em D. saccharalis. Por outro lado, a proporção de fêmeas em relação a machos de C. flavipes foi maior no tratamento onde as lagartas foram alimentadas com dieta contendo 0,5% de inibidores semi-purificados comparado-se à testemunha. A proporção fêmea:macho foi significativamente maior também quando os parasitóides foram alimentados com o inibidor do tipo Kunitz em relação ao controle e aos parasitóides alimentados com BBI. A adição de 0,5% (p/v) de inibidores de proteinases semi-purificados e 0,05% (p/v) de inibidores purificados do tipo Kunitz nos meios de cultura MC e BDA resultaram em maiores crescimento vegetativo e produção de conídios de M. anisopliae. Os inibidores purificados do tipo BBI não alteraram a esporulação do fungo. Os resultados dos estudos com A. mellifera não foram conclusivos e novas investigações precisam ser conduzidas para esclarecer os potenciais efeitos de inibidores de proteinases em abelhas. De uma forma geral, observou-se que os inibidores de proteinases (Kunitz e BBI) não afetaram negativamente os organismos não-alvo testados. Por outro lado, a ingestão de inibidor do tipo Kunitz alterou positivamente alguns parâmetros biológicos de C. flavipes, M. anisopliae e S. praeincisus. / Genes of plants expressing insect proteinase inhibitors have been introduced into plants for pest control. Proteases inhibitors are present in plant tissues, mainly in seeds, and act in response to predators and pathogens. The Bowman-Birk type and Kunitz type of serine proteases inhibitors (PI) from soybean seeds are been used to increase resistance of sugarcane to Diatraea saccharalis (Fabr.), the most important pest of this crop. The sustainability and environmental safety of PI crops is still unknown. For these reasons, it is necessary to understand the stability and the non-target effects of this new trait. The objective of this study was to evaluate the direct and indirect effects of soybean PI on the following non-target organisms associated to sugarcane: the larval parasitoid, Cotesia flavipes (Cam.) (Hymenoptera: Braconidae); the entomopathogen, Metarhizium anisopliae (Mestch.) Sorokin (Deuteromycotina: Hyphomycetes); the pollinator Apis mellifera L. (Hymenoptera: Apidae) and the soil mite involved in the process of recycling organic matter, Scheloribates praeincisus (Berlese) (Acari: Oribatida: Scheloribatidae). Kunitz and BBI did not affect S. praeincisus survival. On the other hand, Kunitz semi-purified and purified inhibitor ingestion reduced duration of the immature stages of S. praeincisus. Ingestion of GM senescent leaves did not have an effect on mite immatures development time and survival compared to ingestion of its isolines leaves. The semi-purified and purified proteinases inhibitors did not alter either the duration of larval and pupal stages of C. flavipes on D. saccharalis, or weight and number of pupae and parasitoid emergence. In other hand, the parasitism and proportion of female was higher on the treatment where caterpillars were fed with diet containing 0.5% of semi-purified inhibitors, comparing to control. The ratio female:male was significantly higher also when parasitoids were fed to the Kunitz type inhibitor compared to the control and BBI. The addition of 0.5 % (w/v) of semi- purified proteinase inhibitors and 0.05% (w/v) of Kunitz type purified inhibitors on two culture media (CM and PDA), resulted in increase of vegetative growth and production of conidia. BBI type purified inhibitors did not change the fungus sporulation. The results from the studies with A. mellifera were not conclusive and investigations are needed to clarify the potential impact of proteinase inhibitors on A. mellifera. Overall, proteinase inhibitors (Kunitz and BBI) did not negatively affect the non-target organisms tested. Conversely, ingestion of the Kunitz type of proteinase inhibitors altered positively some biological parameters of C. flavipes, M. anisopliae and S. praeincisus.

Orientadores: Sergio Marangoni, Luis Alberto Ponce Soto / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-22T22:19:51Z (GMT). No. of bitstreams: 1 VilcaQuispe_Augusto_D.pdf: 3256672 bytes, checksum: 5fbbaf997230230025e7a3945d3d9410 (MD5) Previous issue date: 2013 / Resumo: No presente trabalho duas novas serinoproteases com atividade trombina-simile, nomeadas TLBbz e TLBro isoladas a partir de Bothrops brazili e Bothrops roedingeri respectivamente, foram purificadas em um único passo cromatográfico por HPLC de fase reversa com um alto grau de pureza e homogeneidade molecular, sem perda da atividade biológica. Ambas serinoproteases foram caracterizadas fisico-quimicamente, revelando uma massa molecular relativa de TLBbz = 35,13 KDa e TLBro = 20,24 KDa por SDS-PAGE. Ambas apresentaram atividade proteolítica perante o substrato cromogenico DL-Ba?NA. Os estudos da atividade cinética mostraram que as serinoproteases tiveram um comportamento michaeliano frente ao substrato DL-Ba?NA, apresentando uma Vmax = 1,89 nmoles ?-NA/Lt/min e KM = 0,853 mM para TLBbz; e Vmax = 0,0432 nmoles ?-NA/Lt/min e KM = 0,039 mM para TLBro. Ambas serinoproteases apresentam uma atividade ótima em torno de 38 oC e pH 8,0; sendo inibidas pela ação do fluoreto de fenilmetilsulfonila (PMSF) e outros inibidores, através dos quais a atividade trombina-simile foi reduzida em mais dos 50 % (TLBbz = 86.2 % and TLBro = 42.6 %). Ambas TLBbz e TLBro possuem caráter acido ao apresentar um elevado numero de aminoácidos ácidos, assim como uma boa quantidade em numero de aminoácidos hidrofóbicos, o que garante a estabilidade conformacional da proteína. A presença de 12 cisteinas sugere a possível formação de 6 pontes dissulfeto. TLBbz e TLBro evidenciaram uma atividade fibrinogenolitica frente ao fibrinogenio bovino hidrolisando a cadeia alfa (?) e beta (?), comportando-se como uma trombina-simile tipo AB no caso da TLBro e tipo B, por hidrolizar a cadeia beta (?), no caso da TLBbz. Finalmente, estudos da atividade biológica indicam a propriedade de induzir agregação plaquetaria e esse efeito e inibido pela presença de PMSF / Abstract: In this work, two new serine proteases with thrombin-like activity called TLBbz and TLBro from Bothrops brazili and Bothrops roedingeri respectively were purified in a single chromatographic step by reverse phase HPLC with a high degree of purity and molecular homogeneity without loss of biological activity. Both serine proteases have been characterized physico-chemically, showing a relative molecular mass of TLBbz = 35.13 and TLBro = 20.24 kDa by SDS-PAGE. On the other hand, showed a proteolytic activity towards the chromogenic substrate DL-Ba?NA. The studies of the kinetic activity showed that serine proteases have a michaelian behavior when tested with the substrate DL-Ba?NA, with a Vmax = 1.89 nmoles ?- NA/Lt/min and KM = 0.853 mM for TLBbz, and Vmax = 0.0432 nmoles ?-NA/Lt/min and KM = 0.039 mM for TLBro. Both serine proteases have an optimal activity around 38 °C and pH 8,0; and were inhibited by the action of phenylmethylsulfonyl fluoride (PMSF) and other inhibitors, whereby the thrombin-like activity was reduced in more than 50 % (TLBbz = 86.2 % and TLBro = 42.6 %). Both TLBbz and TLBro have acidic character by presenting a large number of aminoacids acids and a good amount of hydrophobic amino acids, which ensures the conformational stability of the protein. The presence of 12 cysteines suggests the possible formation of six disulfide bridges. TLBbz and TLBro showed a fibrinogenolytic activity against the bovine fibrinogen and hidrolise alpha (?) and beta (?) chain, behaving as a thrombin-like AB types in the case of TLBro and hydrolyzing the beta chain (?) behaving as a thrombin-like B types in the case of TLBbz. Finally, studies of biological activity indicate the ability to induce platelet aggregation and this effect is inhibited by the presence of PMSF / Doutorado / Bioquimica / Doutor em Biologia Funcional e Molecular

Doctor of Philosophy / Department of Entomology / Ming-Shun Chen / Gerald E. Wilde / Analysis of transcriptomes from salivary glands and midgut of the Hessian fly [Mayetiola destructor (Say)] identified a diverse set of cDNAs that were categorized into five groups, group I – V, based on their phylogenetic relationship. All five of these groups may encode putative protease inhibitors based on structural similarity with known proteins. The sequences of these putative proteins among different groups are highly diversified. However, sequence identity and structural analysis of the proteins revealed that all of them contained high cysteine residues that were completely conserved at their respective positions among these otherwise diversified proteins. Analysis of bacterial artificial chromosome (BAC) DNA for two groups, group I (11A6) and group II (14A4), indicated that group I might be a single copy gene or genes with low copy number whereas group II exists as multiple copies clustered within the Hessian fly genome. To test the inhibitory activity and specificity of these putative proteins, recombinant proteins were generated. Enzymatic analysis of the recombinant proteins against commercial and insect gut proteases demonstrated that recombinant proteins indeed are strong inhibitors of proteases with different specificities. Northern analysis of the representative members of five groups revealed that the group I-IV genes were expressed exclusively in the larval stage with variations among groups at different larval stages. The group V (11C4) genes were expressed in the late larval and pupal stage. Tissue specific gene expression analysis revealed that group I-IV genes were predominantly expressed in malpighian tubules whereas the group V genes were abundantly expressed in the salivary glands. Localization experiments with the antibody for representative members from group II (14A4) demonstrated that the protein was predominantly localized in the malpighian tubules and in low amounts in the midgut, suggesting that malpighian tubules are the primary tissue of 14A4 inhibitor synthesis. The overall results indicated that the Hessian fly contains a complex network of genes that code for protease inhibitors which regulate protease activities through different developmental stages of the insect.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-07-28T13:17:05Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO.pdf: 1904426 bytes, checksum: 881aba48363b69adb462f39f38edbbe8 (MD5) / Made available in DSpace on 2017-07-28T13:17:05Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO.pdf: 1904426 bytes, checksum: 881aba48363b69adb462f39f38edbbe8 (MD5) Previous issue date: 2016-02-23 / As proteases são enzimas com a capacidade de hidrolisar proteínas em peptídeos menores ou aminoácidos livres, sendo essenciais para animais, plantas e micro-organismos devido à sua atuação na regulação metabólica. As proteases são utilizadas com diversas finalidades, no processo industrial da fabricação de detergentes, na indústria farmacêutica e de alimentos, além de ser utilizada na recuperação e aproveitamento de resíduos e subprodutos. Em virtude da grande importância das proteases este trabalho teve como objetivo comparar a produção de proteases produzidas por Mucor subtilissimus UCP 1262 em fermentação em estado sólido (FES) e submersa (FS), bem como extrair em Sistema de duas fases aquosas (SDFA) PEG/Fosfato, as colagenases oriundas de ambas as fermentações. O meio de produção da FES e FS no qual o micro-organismo foi cultivado era constituído principalmente de farelo de soja e farinha de soja. As determinações enzimáticas e dosagem proteica foram realizadas após 72h de fermentação. Para montagem do SDFA foram realizados dois planejamentos fatoriais 23, o primeiro planejamento foi realizado com amostras da FES e o segundo com amostras da FS. Neste sistema foi analisada a influência de três variáveis no processo de extração: massa molar do PEG (200, 550 e 1000 g/mol), concentração do PEG (17,5; 20 e 22,5%) e concentração do sal fosfato de sódio (15; 17,5 e 20%). A maior produção de proteases (362,66 U/ml) ocorreu na FES, enquanto que na FS obteve-se apenas 26,33 U/ml. Dentre as atividades proteásicas específicas: colagenolítica, fibrinolítica e queratinolítica, os melhores resultados foram obtidos para a atividade colagenolítica, sendo esta de: 179,81 U/ml, em FES. A colagenase presente no extrato bruto obtida nos processos fermentativos foram particionadas para fase rica em PEG do SDFA. O maior valor para a variável resposta Fator de purificação (FP=3,49) foi obtido no sistema que utilizou o extrato obtido por FES. Com base nas condições estudadas, os dois sistemas mostraram-se viáveis para a extração de colagenase, pois além de ser um processo que pode ser utilizado em larga escala é constituído por componentes de baixo custo e as condições utilizadas no SDFA favoreceram a extração desta enzima. Todavia, a extração da colagenase oriunda da FES foi mais promissora em virtude da maior concentração da enzima de interesse encontrada nesse tipo de fermentação. / Proteases are enzymes with the ability to hydrolyze proteins into smaller peptides and free amino acids. They are vital for animals, plants and micro-organisms due to their role in metabolic regulation. Proteases have been used in various purposes, in the industrial process of detergents, pharmaceutical and food industry, as well as being used in the recovery and utilization of waste and by-products. Due to their economic feasibility and great medical and farmaceutical importance this study aimed to compare the production of proteases produced by Mucor subtilissimus UCP 1262 in solid state fermentation (SSF) and submerged fermentation (SF) as well as extract collagenolytic proteases using Aqueous two-phase system (ATPS) -PEG/Phosphate from both fermentations. The medium composition for the fungal fermentation in SSF and SF was based in soybean flour. Enzymatic determinations and protein levels were performed after 72 hours of fermentation. To mount the ATPS were two 23 factorial design, the first planning was carried out with samples of SSF and the second with samples of SF. In this system was analyzed the influence of three variables in the extraction process: PEG molar mass (200, 550 and 1000), the PEG concentration (17,5; 22,5 and 20%) and sodium phosphate salt concentration (15; 17,5 and 20%). The higher proteolytic activity (362,66 U/ml) was produced using SSF, while in the FS was obtained 26,33 U/ml. Among the specific proteolytic activities: collagenolytic, fibrinolytic and keratinolytic, the best results were obtained for the collagenolytic activity, this being: 179,81 U / ml in the SSF. The Collagenase present in the crude extract obtained in the fermentative processes partitioned preferencially to the PEG-rich phase. The highest value for the variable response Purification Factor (PF = 3,49) was obtained in the system that used SSF crude extract. According with the showed results, both extraction systems seemed to be feasible for collagenase extraction, as well as being a process that can be used in large scale, constituted by low cost components and conditions used in this ATPS favored the enzyme extraction. Furthermore, the collagenase extraction from the SSF was more promising because of the higher interest enzyme concentration found in this type of fermentation.

Ce travail porte sur le développement de sondes peptidiques pour le suivi de la protéolyse par spectroscopie de résonance paramagnétique électronique (RPE) et pour l'imagerie in vivo par résonance magnétique rehaussée de l’effet Overhauser (OMRI). Plus précisément, ce travail étudie pour la première fois une famille d’agents d’imagerie appelée « nitroxyde à déplacement de raies spectrales » spécifique d’activités enzymatiques. L'activité protéolytique, entraînant un décalage de 5 G dans les constantes de couplages hyperfins, permet une quantification individuelle des espèces substrat et produit par RPE et une excitation sélective par OMRI. Trois substrats ont été élaborés, montrant une spécificité enzymatique pour l’élastase du neutrophile (NE) (MeO-Suc-Ala-Ala-Pro-Val-Nitroxyde & Suc-Ala-Ala-Pro-Val-Nitroxyde), et pour la chymotrypsine et la cathepsine G (Suc-Ala-Ala-Pro-Phe-Nitroxyde). Les constantes enzymatiques ont montré de bonnes valeurs avec globalement, Km = 28 ± 25 µM et kcat = 19 ± 3 s-1. Ex vivo, l’utilisation des substrats NE en OMRI a révélé un contraste élevé dans les lavages broncho-alvéolaires de souris sous stimulus inflammatoire. Les rehaussements de signaux IRM sont en corrélation avec la sévérité de l’inflammation. L'irradiation à la fréquence RPE de 5425,6 MHz a permis d'accéder à la bio-distribution des substrats in vivo et pourrait ainsi servir d’outil diagnostic. Les perspectives à moyen terme de ce travail reposent sur le développement de l’OMRI à très faibles champs magnétiques en vue d’une application chez l’homme. / This work focuses on substrate-based probes for proteolysis monitoring by Electron Paramagnetic Resonance spectroscopy (EPR) and for in vivo imaging by Overhauser-enhanced Magnetic Resonance (OMRI). More precisely, this work investigates for the first time a family of MRI agents named “line-shifting nitroxide” specific for proteolytic activities. Proteolytic action results in a shift of 5 G in EPR hyperfine coupling constants allowing individual quantification of substrate and product species by EPR and selective excitation by OMRI. Three substrates were worked out, showing enzymatic specificity for neutrophil elastase (MeO-Suc-Ala-Ala-Pro-Val-Nitroxide & Suc-Ala-Ala-Pro-Val-Nitroxide), and for Chymotrypsin/Cathepsin G (Suc-Ala-Ala-Pro-Phe-Nitroxide). Enzymatic constants were remarkably good with globally Km = 28 ± 25 µM and kcat = 19 ± 3 s-1. Ex vivo, the use of NE substrates in OMRI revealed a high contrast in bronchoalveolar lavages of mice under inflammatory stimulus. MRI signal enhancements correlate with the severity of inflammation. Irradiation at the RPE frequency of 5425.6 MHz provided access to the bio-distribution of substrates in vivo and could thus serve as a diagnostic tool. The medium-term perspectives of this work are based on the development of OMRI with very low magnetic fields for human application

L’hypoxie-ischémie (HI) et l’inflammation sont les principaux facteurs de risques d’apparition de paralysies cérébrales (PC) chez le nouveau-né prématuré ou à terme. La PC est un ensemble de troubles moteurs et cognitifs nécessitant une prise en charge à vie. Sa prévalence en Europe est de 1,7‰ naissances vivantes, ce qui constitue un problème de santé publique. Les nouveau-nés prématurés et nés à terme montrent des atteintes structurales et des déficits à long terme différents aux plans quantitatif et qualitatif. À ces âges, les interventions thérapeutiques et de prévention sont limitées du fait des interférences probables avec le développement. Afin d’appréhender les mécanismes de ces lésions périnatales et de trouver de potentielles pistes d’intervention précoce, nous avons utilisé un modèle murin d’HI chez la souris de 5 et 10 jours (P5 et P10). À ces stades, le développement cortical chez la Souris mime celui d’enfants prématurés (vers 30 SG) ou à terme. Méthode. Afin d’étudier la réponse différenciée à l’HI entre ces deux stades, nous avons, dans un premier temps, réalisé une étude longitudinale par imagerie IRM suivie d’une étude comportementale des animaux à l’âge adulte, ainsi que des études enzymatiques ciblées en période périnatale. Dans un second temps, nous avons réalisé une étude globale et sans apriori des modifications précoces du transcriptome. Résultats I. Nos résultats renforcent la validité de ce modèle murin pour l’étude des lésions spécifiques correspondant aux lésions : soit de nouveau-nés prématurés soit d’enfants à terme. En effet, nous montrons une atteinte spécifique de la substance blanche (SB) chez les souris à P5, mimant les leucomalacies périventriculaires du grand prématuré. Nous montrons que l’atteinte de la SB est associée à une vulnérabilité vasculaire dépendante de l’âge. L’atteinte vasculaire passe par l’activité de la MMP-9, sous dépendance du tPA. À long terme, nous montrons des atteintes cognitivo-comportementales dépendantes de l’âge, permettant d’associer les lésions de la SB aux déficits d’interaction sociale et à l’hyperactivité, alors que les déficits d’apprentissage sont plus amples chez la souris exposée à l’HI à P10 et sont associés à des lésions de l’hippocampe et du cortex rétrosplénial. Résultats II. L’étude du transcriptome a permis de constituer une base de données utilisable pour des études ultérieures. Elle montre des différences importantes de la réponse induite par l’HI, en fonction de l’âge. Cinq faits parmi les plus marquants sont à retenir : i) si les processus affectés aux deux âges sont les mêmes, soit principalement la régulation de la transcription, l’inflammation, la mort cellulaire et l’angiogenèse, les gènes mis en jeu sont sensiblement différents, ii) une réponse à P10 qui, pour une grande partie, s’oppose à l’évolution ontogénique des niveaux de transcrits, peut être le signe d’un arrêt dans le processus de développement, iii) des cinétiques d’induction et de répression différentes à P5 et P10, la réponse étant retardée à P10 en termes de délai d’induction et de maximum d’amplitude, iv) la réponse transcriptomique à l’HI à P5 semble en voie d’extinction après 24h, alors qu’à ce même délai post-HI, la réponse montre une forte amplification chez les animaux lésés à P10, v) une répression coordonnée, à P5 seulement, de gènes codant des protéines impliquées dans les fonctions synaptiques 12h après l’HI, potentiellement responsable de l’extinction de la réponse à 24h. Conclusion. Ces études, complémentaires, permettent une meilleure compréhension de la pathogenèse des lésions cérébrales néonatales. Elles ouvrent notamment différentes pistes de recherche pour les années à venir, orientées vers : i) la spécificité vasculaire, dépendante de la structure et du stade de développement, ii) la prise en compte du stade de développement pour l’expérimentation et la mise au point de stratégies de neuroprotection spécifiques de l’âge. / Hypoxia-ischemia and inflammation are the major triggers of cerebral palsy (CP) in preterm and term new-born. CP is defined as a group of nonprogressive disorders of movement and posture, associated with cognitive and behavioural disorders. CP prevalence is about 1.7‰ living birth and leads to life-long medical care which altogether makes CP a healthcare issue. Preterm and term new-born exhibit specific structural damages and long-term outcomes. In the perinatal period, therapeutic or preventive strategies are limited due to the risk of interference with the ongoing development. To further explore lesion mechanisms, we used the well described “Rice-Vannucci” model of HI adapted in mice aged 5 or 10 days (P5/P10). At these developmental stages, mouse cortical development mimics those of human preterm and term new-born respectively.Methods. To explore the differentiated response to HI between P5 and P10 mice, we first performed a longitudinal MRI study associated with learning and social behaviour testing at adulthood. We also used targeted enzymatic approaches in perinatal period. In a second time, we performed a global, non-targeted assessment of early HI-induced transcriptome modifications during the first 24h after HI.Results I. Our results validated the HI model for the study of age-dependent lesions corresponding to preterm or term new-born lesions. We confirmed the P5-specific white matter lesions mimicking periventricular leukomalacia of preterm infants (30GW). We showed that these white matter lesions originate from age-dependent vascular vulnerability. This vascular vulnerability involved P5 restricted vascular MMP-9 activity which also depends on tPA activity. We showed age-dependent long-term cognitivo-behavioural outcomes, allowing us to associate white matter damages to social behaviour and hyperactivity, whereas learning deficits were more pronounced in P10 mice and associated with hippocampal and retrosplenial cortex damages.Results II. The transcriptome study has generated a useful database for further research. It also showed very important differences in HI-induced transcriptomic responses. Five highlights emerged: i) identical processes (pathways, GO terms) were affected by HI in both P5 and P10 mice: i.e. regulation of transcription, inflammation, cell death/apoptosis and angiogenesis, but the genes induced or repressed associated to these processes were highly different at the two stages, ii) the HI-induced transcription response at P10 mainly counteracted the development-induced transcription changes, iii) the kinetics of induction/repression were different between P5 and P10 mice; P10 mice exhibiting a global delayed response to HI compared to P5 in terms of delay of induction/repression and maximum amplitude, iv) twenty-four hours after HI, the response at P5 was slowing down, apparently returning to basal state, whereas in P10 mice the changes appeared uncontrolled, v) a P5 specific coordinated repression of genes coding proteins involved in synaptic function was observed 12h post-HI, perhaps at the origin of the global slowing-down of transcription alterations observed 24h post-HI.Conclusion. These complementary studies provide a better understanding of the pathogenesis of neonatal brain injury. They also open routes towards new research areas such as: i) the specific vascular vulnerability, depending on brain structures and developmental stage, ii) the consideration of the maturation stage in the further development and experimentation of new neuroprotective strategies.

The hard tick Ixodes ricinus is an important blood-feeding parasite that transmits tick- borne diseases, such as tick-borne encephalitis and Lyme disease. Ticks employ a battery of proteolytic enzymes, including cathepsins, to digest their bloodmeal. These proteins are potential targets for the development of anti-tick vaccines. This work is focused on cathepsin L from I. ricinus (IrCL), namely its isoenzymes IrCL1 and IrCL3. IrCL1 was expressed in Pichia pastoris and chromatographically purified. Its substrate specifity was determined by the cleavage of (a) peptide fluorogenic substrates and (b) protein substrates analyzed by mass spectrometry. The proteolytic activity of IrCL1 was modulated by its interaction with glycosaminoglycans, which affected the pH optimum value. Futhermore, a proteolytically active mutant of IrCL1 with reduced number of N-glycosylation sites was prepared; this form will be used for crystallization experiments. IrCL3 was expressed in Escherichia coli, refolded and activated to its active form. The proteolytic activity of IrCL3 is in many ascpects similar to that of IrCL1, including substrate specifity, acidic pH optimum and activity modulation by glycosaminoglycans. Key words: cysteine proteases, cathepsin L, hard tick I. ricinus, substrate specifity, proteolytic activity...

<p>Deep vein thrombosis (DVT) and Pulmonary embolism (PE) are responsible for over 900,000 cases and 100,000 deaths each year in the US. Direct fibrinolytic agents such as plasmin are being investigated for their treatment. However, plasmin administration is not widely studied as low plasmin concentrations are rapidly inactivated by antiplasmin in vivo, whereas high plasmin doses would deplete endogenous antiplasmin and impose bleeding risks. Thus, a plasmin delivery system that can achieve efficient clot lysis while minimizing inactivation by antiplasmin and has reduced bleeding risks is needed. To address this, we propose using reversible inhibitors of plasmin that can sequester plasmin from antiplasmin and release it on the surface of a fibrin clot to achieve clot lysis. The inhibition must be tuned such that it is strong enough to protect plasmin from antiplasmin and weak enough to release plasmin at the clot for lysis. To achieve this, we utilize principles of multivalency to synthesize three classes of inhibitors with varying potencies and mechanisms of inhibition: (i) Multivalent benzamidines (ii) Multivalent tranexamic acids (TXA), and (iii) Hetero-multivalent inhibitors having both benzamidine and TXA. Benzamidine is a competitive inhibitor of plasmin’s active site. TXA, on the other hand, is an FDA-approved weak active site inhibitor that is primarily used to disrupt plasmin(ogen) from binding to fibrin on the clot by inhibiting plasmin’s kringle domains. Multivalent inhibitors were synthesized using amine-reactive chemistry, purified using RP-HPLC and confirmed with Mass Spectrometry. Inhibition assays were performed to assess inhibition potency by determining Ki values (inhibition constants). Lower Ki values indicate stronger inhibition. With multivalent benzamidine derivatives, it was observed that changing valency and linker length substantially impacted inhibition and resulted in Ki values ranging from 2.1 to 1,395 μM. Inhibitors of higher valencies and shorter linker lengths exhibited stronger inhibition. Multivalent TXAs of valencies 1 to 16 were also tested and they exhibited Ki values varying from 2.5 to 21,370 μM indicating up to 8,548-fold improvement in inhibition due to valency. It was found that monovalent TXA, primarily a kringle inhibitor, can be converted into a stronger active site inhibitor by multivalency. With hetero-bivalent TXA-dPEG36-AMB, simultaneous binding of benzamidine to the active site and TXA to the kringle domains was achieved to attain improved inhibition. These results indicate that multivalency can significantly alter the potency of inhibitors and can modulate plasmin inhibition for drug delivery.</p>