TCC - Bacharelado em Ciências Biológicas (Sede)
URI permanente para esta coleçãohttps://arandu.ufrpe.br/handle/123456789/412
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Item Análise da Influência do número de cópias na expressão do gene blaKPC(2021-03-05) Oliveira, Michelly Maria Pereira e; Almeida, Anna Carolina Soares; http://lattes.cnpq.br/4153747599532886Enterobacteria has stood out in clinical practice by detecting enzymatic mechanisms that confer resistance to antimicrobials, especially Klebsiella pneumoniae carbapenemase (KPC) due to its rapid worldwide dissemination caused by the location of the blaKPC gene in large transferable plasmids and transposons. The expression of the blaKPC gene can be affected by intrinsic characteristics of the host that hosts it or the number of copies. An unusual phenotype was observed in clinical isolates of P. stuartii and M. morganii and their respective transformants, where E. coli cells that received plasmids that carried the blaKPC gene, showed MIC values, for some beta- lactams, higher than in clinical isolates. The objective of this work was to analyze the number of copies of the blaKPC gene, relating them to their respective MICs. The genomic DNA of the bacterial isolates was extracted from the PromegaTM WizardTM Genomic DNA Purification kit according to the manufacturer's guidelines, and was then quantified by spectrophotometry using the NanoDropTM Lite equipment from Thermo Fisher Scientific. The endogenous control genes were chosen from the literature after a robust search, after which they were analyzed in silico. Using databases, software and other tools, primers were designed. To carry out absolute quantification, an estimate was made based on a proportion of the relative quantitative relationship between target and endogenous control, using the formula 2-ΔCq. For the experiments, the SteponeTM Real-time PCR System (Applied Biosystems) and the SYBR Green PCR Master Mix (Applied Biosystems) were used. The designed primers underwent a validation step to evaluate their efficiency (tufMm - 93,019, tufPs - 90,228 and tufKp - 103,474, both with R2 close to 1). The data generated by the absolute qPCR experiments were associated with the different phenotypic profiles observed and from the tests it was determined that the number of copies of the blaKPC gene for transforming isolates and clinical isolates does not vary significantly, pointing out that another mechanism must be interfering in the expression of the blaKPC gene, directly influencing resistance levels.Item Análise da suceptibilidade aos antimicrobianos em Pseudomonas spp. isoladas de produtos saneantes(2020-02-03) Vitor, Mizânia Cabral de Almeida; Almeida, Anna Carolina Soares; Souza, Paula Mariana Salgueiro de; http://lattes.cnpq.br/6281410502740086; http://lattes.cnpq.br/4891800920829895Item Análise de mecanismos de resistência em bactérias clínicas oriundas de hospitais de Pernambuco(2021-02-17) Silva, Jonas de Melo Silvestre da; Almeida, Anna Carolina Soares; http://lattes.cnpq.br/4891800920829895; http://lattes.cnpq.br/9044602995334190The spread of resistant bacteria or superbugs has been considered a catastrophic threat to the health of the population and represents one of the main challenges in the area of health worldwide. This work's main objective is to identify genetic and molecular determinants, resistance mechanisms, and the clonal relationship between twenty-two isolates obtained from two hospitals in Pernambuco. Isolates of: Klebsiella pneumoniae, Klebsiella ozaenae, Escherichia coli, and Enterobacter spp were included, all of which showed a phenotypic profile of multidrug resistance (MDR). Isolates from the University Hospital of the Federal University of Vale do São Francisco had a higher resistance profile compared to isolates from the University Hospital Oswaldo Cruz located in Recife, mainly to aminoglycosides and 3rd and 4th generation cephalosporins. Using the polymerase chain reaction (PCR) technique, it was possible to detect at least one of the B-lactam resistance genes tested in all isolates, except for 2 isolates that did not present any of the genes evaluated. The blaCTX-M gene was the most prevalent found in this study. And despite half of the samples having a resistance profile to carbapenems, the blaKPC gene was the least detected. In addition, clonal relationship analysis using the REP-PCR technique revealed a possible endemicity of a single clonal type in the Intensive Care Unit at Hospital Universitário Oswaldo Cruz located in Recife. At the University Hospital of the Federal University of Vale do São Francisco, the establishment of two clonal groups that have been disseminated for at least 3 months was identified. The presence of multiresistant bacteria in hospital units reinforces the need for strategies to contain infections and spread these pathogens, especially in ICUs.Item Investigação do potencial antibiofilme da lectina de folhas de Schinus terebinthifolia Raddi contra Staphylococcus aureus(2019-12-20) Silva, Talyta Naldeska da; Pontual, Emmanuel Viana; Silva, Pollyanna Michelle da; http://lattes.cnpq.br/0563176148137978; http://lattes.cnpq.br/1777060469196142; http://lattes.cnpq.br/8762925956752737Biofilms are complex microbial communities that have been associated with the incidence of infections, including in the hospital environment. Its formation is considered a determining factor for virulence in microorganisms and strongly contributes with the microbial resistance to conventional antimicrobials. In this sense, the search for natural compounds with antimicrobial activity that are more effective and less toxic to host cells. Plants are important sources of bioactive compounds, including lectins, a class of carbohydrate-binding proteins whose antimicrobial action has been reported. SteLL is a leaf lectin isolated from Schinus terebinthifolia Raddi (Anacardiaceae) with antimicrobial action that was previously reported. In this work, the antibacterial and antibiofilm potential of SteLL against sensitive (UFPEDA 02) and oxacillin resistant (UFPEDA 670) isolates of Staphylococcus aureus was evaluated. SteLL was a bacteriostatic and bactericidal agent against UFPEDA 02 and UFPEDA 670 isolates with MIC50 (Minimum Inhibitory Concentration) of 12.5 and 25.0 μg/mL and CMB (Minimum Bactericidal Concentration) of 50.0 and 100 μg/mL, respectively. The growth kinetics of the cells treated with SteLL revealed a dose-dependent growth inhibition regarding to control. SteLL caused morphometric alterations in S. aureus cells and inhibited biofilm formation of UFPEDA 02 at concentrations between 400 and 25.0 μg/mL and UFPEDA 670 between 400 and 100 μg/mL. In conclusion, SteLL is an antibacterial agent against Staphylococcus aureus by inhibiting the growth, promoting cell death and inhibiting bacterial biofilm formation.Item Prospecção da atividade antimicrobiana de polissacarídeos extraídos das paredes celulares das leveduras Kluyveromyces marxianus, Kluyveromyces lactis e Saccharomyces cerevisiae(2021-02-26) Araújo, Isabelle Maria Feitosa de; Ferreira, Éder Galinari; http://lattes.cnpq.br/7670722046479986; http://lattes.cnpq.br/5044579569126838Polysaccharides from the most diverse sources, may have pharmacological activities such as, for example, antioxidant, immunomodulatory, anticoagulant and antimicrobial. Bearing in mind that this last activity has not yet been evaluated, according to our bibliographic survey, for the cell wall polysaccharides of the yeasts Kluyveromyces marxianus and Kluyveromyces lactis, the objective of this study was to verify the antimicrobial activity of polysaccharides extracted from the cell walls of the yeasts Kluyveromyces marxianus CCT7735 and Kluyveromyces lactis CBS2359 and compare them to a non-Kluyveromyes yeast like Saccharomyces cerevisiae CAT-1. The susceptibility tests were performed in Petri dishes (90 x 15 mm) using the Kirby-Bauer disc-diffusion method as recommended by the M 100 supplement of the 29th edition of the Clinical & Laboratory Standards Institute. Ten microliters of the polysaccharide solution (10 mg/mL) solubilized in distilled water and sterilized by filtration were deposited on sterile paper discs (6 mm). Polysaccharides were tested against Escherichia coli ATCC 25922 (positive control: 100/10 μg of piperacillin-tazobactam); Staphylococcus aureus ATCC 29213 (positive controls: 30 μg of cefoxitin and 10 units of penicillin); Pseudomonas aeruginosa ATCC 27853 (positive controls: 100/10 μg of piperacillin-tazobactam and 10 μg of gentamicin); Klebsiella pneumoniae ATCC 700603 (positive control: 10 μg gentamicin) and Enterococcus faecalis ATCC 29212 (positive controls: 30 μg tetracycline and 10 units of penicillin). None of the cell wall polysaccharide samples evaluated inhibited the growth of the pathogenic bacteria strains tested. Thus, at least in native molecules, polysaccharides did not show antimicrobial activity. We suggest that further studies be carried out with the samples evaluated, either for other pharmacological applications/activities or with the chemical modification or modification of the concentration of these polysaccharides, followed by a new test for antimicrobial activity, among others.