Histone lysine demethylases comprise an important family of epigenetic regulatory enzymes. They catalyse the demethylation of tri-, di- and monomethylated lysine residues on histone H3, thus contributing to either silencing or activation of chromatin. Their biological roles are widespread and have just begun to be elucidated. Among other functions, they contribute to establishment and maintenance of pluripotent states in embryonic stem cells, and also to cellular differentiation during development. Abnormal expression or mutation of some demethylases has been linked to diverse diseases, from prostate and oesophageal cancers to X-linked mental retardation. The development of small molecule inhibitors of histone demethylases is therefore of interest, both from the therapeutic perspective, and with the aim of developing chemical probes to understand the diverse functions of the demethylases in vivo. Most histone lysine demethylases belong to the 2-oxoglutarate and ferrous iron dependent dioxygenase superfamily. This family utilises molecular oxygen to catalyse hydroxylation of substrates, together with oxidation/decarboxylation of the 2-oxoglutarate cofactor. In the work outlined in this thesis, the JMJD2 family of histone demethylases was characterised biochemically, with attention given to mechanism, substrate selectivity and the role of eo factors. JMJD2E was identified herein as a novel histone demethylase in H. sapiens, and was shown to be selective for the demethylation of tri-, di- and monomethylated lysine 9 in histone H3. JMJD2E was also found to be particularly amenable to mechanistic and inhibition studies in vitro. A variety of mechanistic investigations established details of the catalytic cycle, its substrate selectivity and the role of iron and ascorbic acid as cofactors. Crystallographic analyses were also employed to compare its substrate selectivity to other JMJD2 family members. Assays suitable for the evaluation of inhibitors of the JMJD2 demethylases were then developed. These included a coupled enzyme assay suitable for kinetic measurements, and two mass spectrometric assays for observing inhibitor binding and catalytic activity. A critical review of the 20G oxygenase inhibitor literature carried out, and was then used as a basis for the identification of inhibitor scaffolds for the JMJD2 demethylases. These were characterised both in vitro (using kinetic assays, mass spectrometry and crystallography), and in cell culture. Some were further developed to achieve selective inhibition of the JMJD2 demethylases over the related prolyl hydroxylase PHD2; crystallography was again employed to understand the mode of inhibition of these potent inhibitors. The kinetic assays developed were optimised for use in a high-throughput screen, and a library of 240 000 compounds was screened against JMJD2E. This was the first instance of high-throughput screening against these promising therapeutic targets. Several hit compounds were identified and characterised further in vitro. Finally, alternative means of inhibiting the JMJD2 demethylases were investigated. Compounds were identified that inhibited JMJD2A by ejection of its unique structural zinc ion, thus demonstrating that selective inhibition of the JMJD2 demethylase family is possible. In summary, this work contains the first detailed investigation of a histone demethylase subfamily, and also the first steps towards identifying potent, selective inhibitors of these epigenetic regulatory enzymes.

Nitrogênio é o nutriente mais utilizado mundialmente na agricultura devido promover grandes aumentos de produtividade e de qualidade, porém durante seu uso pode haver perdas de N por lixiviação e volatilização. O uso de inibidores de urease e de nitrificação podem aumentar a eficiência de uso de adubos nitrogenados. Objetivouse: a) estudar doses e fontes de nitrogênio na produção de cana-de-açúcar (Saccharum spp.) colhida sem despalha a fogo e avaliar a resposta desta cultura em aplicação do N na superfície do solo; b) avaliar a eficiência do uso de dicianodiamida em solos de diferentes texturas, com e sem a presença de palha, em estudo de incubação com sulfato de amônio; c) avaliar a eficiência de DCD e DMPP em solos do Brasil e da Alemanha em estudo de incubação e d) avaliar a eficiência de DCD e de NBPT na volatilização de amônia e na taxa de nitrificação de uréia. Houve aumento de produção de colmos de cana-de-açúcar nas doses de 0, 50, 100 e 150 kg ha-1 de N, porém não houve diferença das diferentes fontes nitrogenadas, mesmo havendo redução de volatilização de NH3 da uréia com o uso de NBPT, em torno de 60%. Houve redução da taxa de oxidação de amônio como uso de DCD, com maior eficiência no solo de textura média e, consequentemente menor formação de nitrato. Com a redução da taxa de nitrificação houve uma menor acidificação do solo. Houve redução da população de microrganismos nitritadores com o uso de DCD. O uso de inibidores de nitrificação (DCD e DMPP) retardou o processo de nitrificação em todos os solos (alemão e brasileiros), porém, com uma eficiência bem mais acentuada no solo arenoso. Houve maior eficiência do DCD nos primeiros 10 dias de incubação devido seu maior movimento no solo e no período final de incubação o DMPP foi mais eficiente devido sua menor degradação no solo. O NBPT foi eficiente em reduzir as perdas por volatilização, já o uso de DCD aumentou as perdas de N-NH3 da fonte uréia e diminuiu a eficiência do NBPT quando aplicado em conjunto com este, independente da dose. O DCD foi eficiente em diminuir o processo de nitrificação e não teve influencia na sua eficiência quando foi utilizado em associação com NBPT. / Nitrogen is the most world widely applied plant nutrient in agriculture because promote high yield and quality increases but, during youre using in agriculture losses by volatilization and leaching can occur. By using urease and nitrification inhibitors the nitrogen fertilizers efficiency can be increase. The objectives of this study was: a) study rates and sources of nitrogen fertilizers on sugarcane (Saccharum spp.) production harvested without burning and evaluate the response of this crop to over trash applied N; b) evaluate the efficieny of using DCD in different texture soils, with or without sugarceane trash, in a icubation experiment with amonium sulphate; c) evaluate the efficiency of DCD and DMPP in Brazilian and German soils in a incubation experiment and d) evaluate the efficiency of DCD and NBPT on ammonia volatilization and nitrification process of urea. Sugarcane yields increase with 0, 50, 100 and 150 kg ha-1 de N rates, but not with different N sources. With using NBPT ammonia volatilization was about 60% less, but also didnt increase sugarcane yield. Ammonium oxidation process in incubation study was inhibited with DCD use and, this inhibition was high in the soil with less clay. With reduction in nitrification process acidification of soil was lower. It was less nitrification microorganisms in soil with using DCD. With nitrification inhibitors (DCD and DMPP) the nitrification processa was delayed in all soils (german and brazilians), especially in sandy soil. DCD was more efficient in the next 10 days because have more mobility in soil wile DMPP was more efficient in the end of nitrification process because is more persistent in soil by his slow degradation process. The use of NBPT with urea is efficient to reduce ammonia volatilization wile urea treated with DCD these N loss is increased. When urea is treated with DCD and NBPT together the ammonia volatilization less is more than NBPT alone, but less of total ammonia volatilization of urea alone. DCD alone is efficient in inhibit nitrificatio

Orientadores: Nelson Horacio Pezoa Garcia, Denise Calil Pereira Jardim / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-03T19:14:01Z (GMT). No. of bitstreams: 1 Efraim_Priscilla_M.pdf: 836235 bytes, checksum: 197b6ebcb7737d4d06c3ba707d63337d (MD5) Previous issue date: 2004 / Resumo: As sementes de cacau (Theobroma cacao L.) da variedade Forastero são extremamente ricas em compostos fenólicos, que representam em média 15 a 20% de seu peso seco e desengordurado, sendo que 60% pertencem à classe dos flavonóides, compostos apontados atualmente como responsáveis pela prevenção de doenças coronárias, diminuição do colesterol sérico, auxiliadores do sistema imunológico, entre outros. Durante a etapa de fermentação, são perdidos, em média, 70% dos flavonóides devido a importantes reações bioquímicas que ocorrem principalmente pela diminuição do pH, aumento de temperatura (45-50°C) e atuação de certas enzimas presentes no fruto ou produzidas pelos microrganismos que participam desta etapa. Tais reações são, em parte, responsáveis pela redução do amargor e da adstringência melhorando assim o desenvolvimento do sabor do chocolate. Desta forma, o presente trabalho visou modificar a etapa de fermentação de sementes de cacau para a produção de chocolate rico em flavonóides sem prejudicar seu sabor. Para isso, procurou-se inibir as enzimas que são possivelmente as principais responsáveis pela perda dos flavonóides através da adição de inibidores químicos (bissulfito de sódio e sulfato cúprico) na etapa de fermentação. Foram realizados sete experimentos distintos: ensaios A e G (fermentações convencionais com duração de 7 e 3 dias respectivamente); ensaios B, C e F (fermentações por 7 dias, modificadas com adição de 5mg, 10mg e 5mg de bissulfito de sódio/100g de massa de sementes com polpa após 48hs, 48hs e 120hs respectivamente e ensaios D e E (fermentações por 7 dias modificadas com adição de 5mg e 10mg de sulfato de cobre/100g de massa de sementes com polpa após 48 horas do início respectivamente). Os resultados indicaram que, de uma forma geral, todos os tratamentos propostos mantiveram maior teor de compostos fenólicos em relação à fermentação convencional (ensaio A). Quanto aos compostos fenólicos totais, o ensaio D apresentou a maior retenção (62,70%) desde o início da fermentação ao término da secagem, enquanto que no ensaio A foram retidos 36,38% destes compostos. Em relação aos flavan-3-óis e procianidinas, observou-se maior retenção, para monômeros, nos ensaios D (34,27%) e G (33,72%); para dímeros, nos ensaios D (21,83%) e G (21,78%); para trímeros, nos ensaios C (22,85%), D (22,37%) e F (22,38); para quatrâmeros, nos ensaios C (25,84%), D (24,77%) e F (27,21) e para pentâmeros, nos ensaios C (35,24%), D (34,45%) e F (34,16). Observou-se que a maior perda dos compostos fenólicos estudados ocorreu entre o término da fermentação e a secagem. Verificou-se que o residual de Cobre remanescente da adição feita durante a fermentação (ensaios D e E) nos liquors e nos chocolates produzidos foi de 0,23 e 0,36mg de cobre/100g de liquor (ensaios D e E respectivamente) e 0,025 e 0,036mg de cobre/100g de chocolate (ensaios D e E respectivamente), todos valores consideravelmente inferiores ao Limite Máximo Tolerado (LMT) definido pela Agência Nacional de Vigilância Sanitária (ANVISA), correspondente a 3,0mg de cobre/100g de amostra. Os chocolates produzidos a partir dos ensaios B, C, D e E mostraram aceitabilidade sensorial igual ou melhor ao convencional (A), enquanto que os produzidos a partir dos ensaios F e G apresentaram aceitabilidade mediana e incertezas com relação a intenção de compra / Abstract: Cocoa seeds (Theobroma cacao L.) from the Forastero variety are very rich in phenolic compounds which represent 15-20% of the defatted dry weight. The principal compounds are (+)-catechin, (-)-epicatechin and 60% of procyanidins that belong to the flavonoid class. These compounds are currently been considered responsible for coronary heart disease prevention, lowering the serum cholesterol and helping the immunological system. During the fermentation, 70% of the total phenolic compounds are lost in important biochemical reactions accelerated by the reduction in pH, temperature increase (45-50°C) and action of some enzymes, present in the fruit or produced by the microorganism growing at this stage. These reactions contribute to a reduction in bitterness and astringency, improving the flavor of the chocolate. The objective of this work was to modify the fermentation stage of cocoa seeds to produce flavonoid-rich chocolates without prejudicing its flavor. This was done by the inactivation of enzymes probably responsible for flavonoid degradation, through the addition of chemical inhibitors (sodium bissulfite and cupric sulphate) during the fermentation stage. Seven experiments were carried out: Experiments A and G (conventional fermentations during 7 and 3 days respectively); experiments B, C and F (modified fermentations during 7 days, with the addition of 5mg, 10mg and 5mg of sodium bissulfite/100g of cocoa seeds with pulp after 48hs, 48hs and 120hs since the beginning of fermentation respectively) and experiments D and E (modified fermentations during 7 days, with the addiction of 5mg and 10mg of cupric sulphate/100g of cocoa seeds with the pulp after 48hs and 120hs since the beginning of fermentation respectively). The results showed that all the treatments proposed maintained higher quantities of phenolic compounds as compared with the conventional experiment (A). Considering the total phenolics, experiment D showed the highest retention (62,70%) from the beginning of the fermentation up to the end of the drying stage, while in the experiment A, the retention was 36,38%. Considering the flavan-3-ols and procyanidins, a higher retention of monomers was observed in experiments D (34,27%) and G (33,72%); of dimers in experments D (21,83%) and G (21,78%); of trimers in experiments C (22,85%), D (22,37%) and F (22,38); of tetramers in experiments C (25,84%), D (24,77%) and F (27,21) and of pentamers in experiments C (35,24%), D (34,45%) and F (34,16). It was observed that the greatest loss of the phenolic compounds studied occurred between the end of fermentation and the beginning of the drying stage. It was shown that the copper residue in the liquor and chocolate remaining from the addition during fermentation (experiments D and E) was 0,23 and 0,36mg of copper/100g of liquor (experiments D and E respectively) and 0,025 e 0,036mg of copper /100g of chocolate (experiments D and E respectively). These values are below the Maximum Tolerated Limit (MTL) defined by ANVISA for this metal (3,0mg/100g). The chocolates B, C, D and E showed equal or better sensory acceptance as compared with conventional (A), and F and G chocolates which showed average sensory acceptance and uncertainty with respect to buying intention / Mestrado / Mestre em Tecnologia de Alimentos

M.Sc. / Proteinases are involved in many cellular reactions involving protein degradation, such as degradation of storage proteins and protein degradation during senescence processes. Their action can be inhibited by proteinase inhibitors. Information is still limited about the regulation of these inhibitors in plants and their possible interaction with proteinases under stress conditions. To obtain a better understanding of the physiological role of a proteinase inhibitor in plants under stress, the expression of a papaya cysteine proteinase inhibitor (cystatin) and its relation to proteinase expression was investigated in more detail. For this purpose, expression of the inhibitor was studied in papaya plants exposed to different physiological stress conditions, such as high/low temperature, and treatment with selected chemicals, such as glutathione, OTC (L-2- Oxothiazolidine-4-carboxylate), bestatin ([(2S, 3R)-3-amino-2-hydroxy-4-phenyl butanoylj-L-leu) and 2.4-D (2,4-dichiorophenoxyacetic acid). Using detection tools like activity gel electrophoresis, immunoblotting and enzymatic assays, the production of the cystatin under stress was monitored in different papaya explants, such as roots, leaves and embryos. Inhibitor production increased under different stress conditions when compared to untreated controls. However, this increase was not dramatic in any of the stresses applied. Exact quantification of the increase by using immunoblotting as the only specific tool to determine cystatin expression, was difficult. Neither activity gel electrophoresis nor enzymatic assays were successful to further quantify the exact cystatin levels. Higher cystatin expression was accompanied with a decrease in proteinase activity. Transgenic tobacco plants carrying the gene for a rice cystatin had a significantly lower cysteine proteinase activity when compared to non-transgenic tobacco plants after prolonged cold stress. Furthermore, protein degradation and leaf yellowing as a consequence of cold treatment were prevented in transgenic plants. An attempt to obtain a transformed papaya plant to study silencing of cystatin expression under stress was unsuccessful. In this study, the protective role of a cystatin in cold stress was described for the first time.

Nitrogênio é o nutriente mais utilizado mundialmente na agricultura devido promover grandes aumentos de produtividade e de qualidade, porém durante seu uso pode haver perdas de N por lixiviação e volatilização. O uso de inibidores de urease e de nitrificação podem aumentar a eficiência de uso de adubos nitrogenados. Objetivouse: a) estudar doses e fontes de nitrogênio na produção de cana-de-açúcar (Saccharum spp.) colhida sem despalha a fogo e avaliar a resposta desta cultura em aplicação do N na superfície do solo; b) avaliar a eficiência do uso de dicianodiamida em solos de diferentes texturas, com e sem a presença de palha, em estudo de incubação com sulfato de amônio; c) avaliar a eficiência de DCD e DMPP em solos do Brasil e da Alemanha em estudo de incubação e d) avaliar a eficiência de DCD e de NBPT na volatilização de amônia e na taxa de nitrificação de uréia. Houve aumento de produção de colmos de cana-de-açúcar nas doses de 0, 50, 100 e 150 kg ha-1 de N, porém não houve diferença das diferentes fontes nitrogenadas, mesmo havendo redução de volatilização de NH3 da uréia com o uso de NBPT, em torno de 60%. Houve redução da taxa de oxidação de amônio como uso de DCD, com maior eficiência no solo de textura média e, consequentemente menor formação de nitrato. Com a redução da taxa de nitrificação houve uma menor acidificação do solo. Houve redução da população de microrganismos nitritadores com o uso de DCD. O uso de inibidores de nitrificação (DCD e DMPP) retardou o processo de nitrificação em todos os solos (alemão e brasileiros), porém, com uma eficiência bem mais acentuada no solo arenoso. Houve maior eficiência do DCD nos primeiros 10 dias de incubação devido seu maior movimento no solo e no período final de incubação o DMPP foi mais eficiente devido sua menor degradação no solo. O NBPT foi eficiente em reduzir as perdas por volatilização, já o uso de DCD aumentou as perdas de N-NH3 da fonte uréia e diminuiu a eficiência do NBPT quando aplicado em conjunto com este, independente da dose. O DCD foi eficiente em diminuir o processo de nitrificação e não teve influencia na sua eficiência quando foi utilizado em associação com NBPT. / Nitrogen is the most world widely applied plant nutrient in agriculture because promote high yield and quality increases but, during youre using in agriculture losses by volatilization and leaching can occur. By using urease and nitrification inhibitors the nitrogen fertilizers efficiency can be increase. The objectives of this study was: a) study rates and sources of nitrogen fertilizers on sugarcane (Saccharum spp.) production harvested without burning and evaluate the response of this crop to over trash applied N; b) evaluate the efficieny of using DCD in different texture soils, with or without sugarceane trash, in a icubation experiment with amonium sulphate; c) evaluate the efficiency of DCD and DMPP in Brazilian and German soils in a incubation experiment and d) evaluate the efficiency of DCD and NBPT on ammonia volatilization and nitrification process of urea. Sugarcane yields increase with 0, 50, 100 and 150 kg ha-1 de N rates, but not with different N sources. With using NBPT ammonia volatilization was about 60% less, but also didnt increase sugarcane yield. Ammonium oxidation process in incubation study was inhibited with DCD use and, this inhibition was high in the soil with less clay. With reduction in nitrification process acidification of soil was lower. It was less nitrification microorganisms in soil with using DCD. With nitrification inhibitors (DCD and DMPP) the nitrification processa was delayed in all soils (german and brazilians), especially in sandy soil. DCD was more efficient in the next 10 days because have more mobility in soil wile DMPP was more efficient in the end of nitrification process because is more persistent in soil by his slow degradation process. The use of NBPT with urea is efficient to reduce ammonia volatilization wile urea treated with DCD these N loss is increased. When urea is treated with DCD and NBPT together the ammonia volatilization less is more than NBPT alone, but less of total ammonia volatilization of urea alone. DCD alone is efficient in inhibit nitrificatio

As plantas desenvolveram diferentes mecanismos para reduzir o ataque de insetos, incluindo compostos protéicos de defesa, como os inibidores de proteinases (IPs). Os insetos, ao longo da evolução, desenvolveram estratégias para superar as barreiras defensivas das plantas, permitindo a sua alimentação e desenvolvimento, como a super expressão de genes de enzimas digestivas sensíveis e insensíveis aos IPs de plantas. Uma das abordagens desse trabalho foi identificar novas serinoproteinases no intestino de lagartas de Spodoptera frugiperda. Duas novas quimotripsinas e trê novas tripsinas foram identificadas e juntamente com mais 10 genes já conhecidos que codificam estas enzimas foram submetidos à análise de expressão gênica por PCR em tempo real. Entre essas duas famílias de serinoproteinases (SPs) os genes que codificam as quimotripsinas apresentam uma regulação positiva mais ampla do que aqueles que codificam as tripsinas. Estudos de modelagem molecular das quimotripsinas também foram realizados. Foram construídos modelos tridimensionais à partir de modelagem por homologia além de análises de dinâmica molecular e docagem com oito diferentes IPs do tipo Bowman- Birk. Os resultados mostram quais quimotripsinas apresentam as maiores afinidades aos inibidores testados de maneira geral e individual, inferidos à partir da estimativa de energia livre do sistema. Também foi encontrada uma serina extra próxima ao sítio catalítico de três quimotrispsinas modeladas que pode interferir na afinidade dessas enzimas já que este aminoácido apresenta perda de área acessível ao solvente quando complexada ao IP de soja testado. Os resultados de expressão gênica e grau de sensibilidade foram comparados e não se observou qualquer relação entre esses parâmentros. Isso sugere que as lagartas da espécie S. frugiperda combinam diferentes estratégias adaptativas como o aumento de expressão de todas as suas quimotripsinas independentemente do grau de sensibilidade das enzimas. / Plants have developed different mechanisms to reduce insect attack, including defence proteins such as proteinase inhibitors (PIs). In turn, insects have evolved strategies to overcome these plant defence mechanisms, such as the hyperexpression of PI-sensitive and insensitive digestive enzymes, allowing the insect to thrive. One of the aims of this work was to identify new serine proteinases (SPs) in the gut of the fall armyworm larvae, Spodoptera frugiperda. Two new chymotrypsins and three new trypsins were identified, and together with 10 previously identified genes, the genes that encode these enzymes were subjected to real-time PCR and gene expression analysis. Between these two families of serine-proteinases the genes that encode chymotrypsins show a greater positive regulation then those encoding the trypsins. Molecular modelling studies of the chymotrypsins were carried out, and 3D models were generated using homology modelling, which were then further refined by dynamic molecular and docking analyses with 8 different Bowman-Birk type PIs. The results demonstrate which chymotrypsins possess the highest affinities to the tested inhibitors in a general and individual manner, inferred from the estimated free energies. A serine residue in very close proximity to the catalytic site was present in three of chymotrypsins investigated, which may be affecting the enzymes affinity since the residue has a reduced accessible area to the solvent when complexed to the soya PI tested. The genetic expression patterns and the degree of PI-sensitivity were also compared and no relation between the parameters was found. This suggests that the larvae of the species S. frugiperda combine different adaptive strategies like the increase in expression of its entire chymotrypsin arsenal regardless of the degree of PI-sensitivity of the enzymes.

As plantas desenvolveram diferentes mecanismos para reduzir o ataque de insetos, incluindo compostos protéicos de defesa, como os inibidores de proteinases (IPs). Os insetos, ao longo da evolução, desenvolveram estratégias para superar as barreiras defensivas das plantas, permitindo a sua alimentação e desenvolvimento, como a super expressão de genes de enzimas digestivas sensíveis e insensíveis aos IPs de plantas. Uma das abordagens desse trabalho foi identificar novas serinoproteinases no intestino de lagartas de Spodoptera frugiperda. Duas novas quimotripsinas e trê novas tripsinas foram identificadas e juntamente com mais 10 genes já conhecidos que codificam estas enzimas foram submetidos à análise de expressão gênica por PCR em tempo real. Entre essas duas famílias de serinoproteinases (SPs) os genes que codificam as quimotripsinas apresentam uma regulação positiva mais ampla do que aqueles que codificam as tripsinas. Estudos de modelagem molecular das quimotripsinas também foram realizados. Foram construídos modelos tridimensionais à partir de modelagem por homologia além de análises de dinâmica molecular e docagem com oito diferentes IPs do tipo Bowman- Birk. Os resultados mostram quais quimotripsinas apresentam as maiores afinidades aos inibidores testados de maneira geral e individual, inferidos à partir da estimativa de energia livre do sistema. Também foi encontrada uma serina extra próxima ao sítio catalítico de três quimotrispsinas modeladas que pode interferir na afinidade dessas enzimas já que este aminoácido apresenta perda de área acessível ao solvente quando complexada ao IP de soja testado. Os resultados de expressão gênica e grau de sensibilidade foram comparados e não se observou qualquer relação entre esses parâmentros. Isso sugere que as lagartas da espécie S. frugiperda combinam diferentes estratégias adaptativas como o aumento de expressão de todas as suas quimotripsinas independentemente do grau de sensibilidade das enzimas. / Plants have developed different mechanisms to reduce insect attack, including defence proteins such as proteinase inhibitors (PIs). In turn, insects have evolved strategies to overcome these plant defence mechanisms, such as the hyperexpression of PI-sensitive and insensitive digestive enzymes, allowing the insect to thrive. One of the aims of this work was to identify new serine proteinases (SPs) in the gut of the fall armyworm larvae, Spodoptera frugiperda. Two new chymotrypsins and three new trypsins were identified, and together with 10 previously identified genes, the genes that encode these enzymes were subjected to real-time PCR and gene expression analysis. Between these two families of serine-proteinases the genes that encode chymotrypsins show a greater positive regulation then those encoding the trypsins. Molecular modelling studies of the chymotrypsins were carried out, and 3D models were generated using homology modelling, which were then further refined by dynamic molecular and docking analyses with 8 different Bowman-Birk type PIs. The results demonstrate which chymotrypsins possess the highest affinities to the tested inhibitors in a general and individual manner, inferred from the estimated free energies. A serine residue in very close proximity to the catalytic site was present in three of chymotrypsins investigated, which may be affecting the enzymes affinity since the residue has a reduced accessible area to the solvent when complexed to the soya PI tested. The genetic expression patterns and the degree of PI-sensitivity were also compared and no relation between the parameters was found. This suggests that the larvae of the species S. frugiperda combine different adaptive strategies like the increase in expression of its entire chymotrypsin arsenal regardless of the degree of PI-sensitivity of the enzymes.