http://repositorio.ufc.br/handle/riufc/21995 2026-04-11T13:46:21Z http://repositorio.ufc.br/handle/riufc/85752 Título: Análise de alvos moleculares da via de biossíntese de nucleotídeos: uma nova abordagem do fármaco mebendazol no tratamento de adenocarcinoma gástrico Autor(es): Lima, Pedro Victor da Rocha Abstract: Gastric cancer (GC) is one of the tumors with the highest incidence and mortality rates globally. The nucleotide pathway plays an indispensable role in maintaining the tumor’s replicative potential by synthesizing DNA and RNA building blocks, which are essential for the tumor cell cycle. Thus, drugs capable of modulating and inhibiting this metabolic pathway are of great clinical interest. Mebendazole (MBZ) was originally described as an anthelminthic drug and has demonstrated potential antitumoral effects, in addition to the capacity to modulate tumor metabolism. However, its effect on the nucleotide metabolism pathway is still poorly understood. This study, therefore, aims to investigate the potential modulatory effect of MBZ on the purine and pyrimidine biosynthesis pathways in the context of GC. The expression profile of the following genes was analyzed: PRPS1, HPRT1, MTHFD1, TYMS, and DHODH, which are responsible for translating into the enzymes that participate in the nucleotide pathway. The AGP-01 cell line showed an elevated transcript level for most of the genes analyzed, specifically: HPRT1, MTHFD1, TYMS, and DHODH. Following contact between the drug MBZ and the tumor cell line, a drop in the expression level for all studied genes was observed. Furthermore, in silico expression studies were analyzed, and the genes PRPS1, HPRT1, MTHFD1, and TYMS showed a high transcript level in clinical samples from GC patients. Patients with high expression of HPRT1, MTFHD1 and TYMS exhibit a worse prognosis, making them targets of clinical interest. Moreover, using molecular docking assays, it was possible to predict the mode of interaction that the ligand MBZ causes with the nucleotide pathway enzymes. The analysis of the results indicated that the anthelminthic drug docked close to the catalytic domain of the enzymes in the in silico assay. The information obtained so far suggests that MBZ demonstrated the activity of modulating the nucleotide biosynthesis pathway by causing a depletion in transcript levels. However, further studies are needed to clarify the interaction behavior of MBZ with the enzymes. Consequently, this work contributes to the exploration and validation of promising new pharmacological targets for the treatment of GC. Tipo: TCC 2025-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/85751 Título: Potencial biotecnológico de actinobactérias do semiárido nordestino na busca por novos agentes antimicrobianos Autor(es): Rocha, Matheus Lucas Santos Abstract: Actinobacteria constitute a group of filamentous microorganisms of significant ecological and biotechnological relevance, widely recognized for their ability to synthesize a vast array of secondary metabolites, including industrial enzymes and antimicrobial agents. Although the genus Streptomyces is the most prominent in the literature overall, the so-called rare actinobacteria comprising morphologically and phylogenetically distinct genera emerge as promising sources for the discovery of new bioactive compounds, as they are less explored and consequently may possess unknown mechanisms, such as biosynthetic pathways for metabolites with antimicrobial activity. In this context, the present study aimed to isolate and characterize the antimicrobial potential of 16 strains of rare actinobacteria, designated as AU (Ubajara Actinobacteria), originating from soil samples of the Caatinga biome in the semi-arid Northeast of Brazil. Initial antimicrobial screening conducted using the cross-streak technique against the pathogens Staphylococcus aureus (ATCC 25923), Salmonella enterica (ATCC 14028), and Klebsiella pneumoniae (ATCC 10031) revealed that four of these strains (AU-1, AU-2, AU-8, and AU-11), corresponding to 25% of the total, exhibited promising inhibitory profiles. These strains were then subjected to fermentation assays under standard conditions and in co-culture, followed by the collection of their cell-free supernatants (CFSs), obtained by centrifugation of the fermented broths. The collected CFSs were reassessed for their antimicrobial potential using the well diffusion method - a more specific step in which only strains AU-2 and AU-8 maintained their antimicrobial activity, with AU-2 demonstrating a notable broadening of its spectrum of action against the tested pathogens. The obtained results not only validate the biotechnological potential of the semi-arid microbiota but also highlight strain AU-2 as a particularly robust candidate for future studies aimed at identifying, purifying, and characterizing the bioactive compounds responsible for its activity, reinforcing the strategic importance of prospecting actinobacteria, especially rare ones, in unique biomes. Tipo: TCC 2025-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/85749 Título: Avaliação funcional de versões engenheiradas do anticorpo comercial rituximabe Autor(es): Saraiva Filho, Plácido Eymard Gomes Abstract: Cancer is one of the main challenges facing global public health. Hematological malignancies, such as lymphomas and leukemias, are characterized by high rates of recurrence and resistance to conventional therapies, factors that make the clinical management of thesediseases particularly complex. In this context, monoclonal antibodies (mAbs) have shown high therapeutic potential, and advances in protein engineering have enabled the development of variants with improved structural and functional properties. In this study, we sought to express and purify mutant variants of the commercial monoclonal antibody rituximab in IgG and scFvFc formats. The mutation of interest, called MUT1 (previously selected by phage display), was proposed by directed evolution via PCR and inserted into the native sequence of rituximab. The DNA of the mutated constructs was transformed into Escherichia coli TOP10 cells for plasmid propagation, which were subsequently isolated and subjected to Sanger sequencing to confirm the genetic modifications. After validation, ExpiCHO cells were transfected with the pcDNA™3.4 plasmid containing the constructs of both formats, allowing recombinant expression of the IgG and scFvFc variants. Purification of recombinant antibodies was performed by affinity chromatography on protein A resin, followed by molecular exclusion chromatography, and the structural integrity and purity of the proteins were confirmed by SDS-PAGE and western blotting. Functional assays by flow cytometry demonstrated that both the native antibody and the MUT1 variant specifically recognized Raji cells, exhibiting a dose-dependent binding profile. Functional assays by flow cytometry demonstrated that both the native antibody and the MUT1 variant specifically recognized Raji cells, exhibiting a dose-dependent binding profile. A consistent trend of increased mean fluorescence intensity was observed for the MUT1 variant at higher concentrations, suggesting a possible functional gain associated with the introduced mutation. Thus, the obtaining and characterization of this variant represent an important step toward the standardization of functional assays and the investigation of the structural and biofunctional effects resulting from the mutation, contributing to the rational development of antibodies with improved therapeutic potential. Tipo: TCC 2025-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/85748 Título: Implementação e melhoria contínua de controle de qualidade de um biofertilizante obtido a partir da fermentação de resíduos da indústria de beneficiamento do camarão Autor(es): Lima, Thalison Vinicius Gomes de Abstract: Population growth has led to a series of environmental and economic concerns. In the agricultural sector, the search for new cultivation alternatives and products capable of accelerating crop growth and mitigating emerging factors that negatively affect agricultural production has become one of the main challenges of the current century. As a result, new ideas have emerged with innovative applications and agile methodologies, such as the use of biological inputs, biofertilizers, and plant biostimulants derived from the fermentative processes of lactic acid bacteria (LAB). The implementation of quality control methods that ensure process efficiency, as well as the quality and purity of the microorganisms used and the standardization of the final product, is mandatory and essential within the industry. Therefore, this study aimed to evaluate, improve, and implement quality control standards and processes applicable to a biofertilizer obtained through a microbiological process from shrimp waste, in accordance with current regulations and legislation. The methodology was based on the implementation of microbiological analyses (viable cell counts, total coliforms, and pathogens) and physicochemical analyses (moisture, ash content, Fourier transform infrared spectroscopy (FTIR), fluorescence microscopy, temperature, and pH) of the raw material, the microorganisms employed, and the final product. The results demonstrated that the implementation of the analytical methods was satisfactory and ensured the safety of the biofertilizer in compliance with legislation for its use as an agricultural bioinput. In addition, the analyses made it possible to identify opportunities for process improvement and standardization, ensuring the safety and traceability of the final product. Thus, the adoption of these methods contributes to the supply of bioinputs with adequate levels of micro- and macronutrients, while also representing a sustainable and efficient alternative to chemical inputs that degrade soil, impact aquatic ecosystems, and reduce the quality of soil microbiota. Consequently, this study highlights the importance of quality control in ensuring safe products aligned with current demands for more sustainable agriculture, as well as in promoting operational efficiency and continuous process improvement. Tipo: TCC 2025-01-01T00:00:00Z