Made available in DSpace on 2015-04-17T15:02:59Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 786983 bytes, checksum: eac9b468ba5f066caa74a9a3589e7b0c (MD5) Previous issue date: 2013-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Staphylococcus aureus is widespread in nature and is the bacteria most often found in skin infections, although it is able to colonize many organ in the human body. This pathogen can also to contaminate food and staphylococcal food poisoning is one of foodborne diseases more common around the world. This study aimed to isolate and characterize samples of S. aureus isolates from surface preparation of meat and vegetables in public hospitals located in the city of João Pessoa - Paraíba - Brazil, as the production of lipase, protease, antibiotic resistance profile and detection of mecA. Further, evaluation was made in the production of lipase strains of S. aureus isolated from animals (udder and nasal cavities), food (cottage cheese) and infected human wounds (hospital). It was observed lipase production in isolates from human wounds (43/50) animals (16/30), cheese (34/41), bench preparation of meat (24/24) and surface preparation plant (22 / 24). All isolates surface preparation of meat, vegetables and cheese produced protease precipitation with zones of diameters ranging from <0.5 to 4 mm. Among the 48 S. aureus isolates from food processing surfaces tested, 100% were sensitive to chloramphenicol, norfloxacin and methicillin. Twelve isolates were resistant to erythromycin and tetracycline, whereas all isolates were resistant to penicillin and streptomycin. The fragment corresponding t the mecA gene was not identified among isolates. The lipolytic and proteolytic activities, as well as antibiotic resistance (even those already with no therapeutic value) constitute important epidemiological and genetic markers may contribute to the characterization of samples environment or host-specific, and, if performed periodically to distinguish those new strains endemic. / Staphylococcus aureus está disseminado na natureza de forma variável, e apresenta-se como a bactéria mais frequentemente encontrada em infecções de pele, todavia é capaz de colonizar quase todos os órgãos do corpo humano. Esse patógeno também pode contaminar alimentos. Intoxicação alimentar estafilocócica é uma das doenças veiculadas por alimentos mais comuns em todo o mundo. Este estudo teve como objetivo isolar e caracterizar amostras de S. aureus isolados de superfícies de preparo de carne e vegetais de hospitais públicos situados na cidade de João Pessoa Paraíba Brasil, quanto a produção de lipase, protease, perfil de resistência a antimicrobianos e detecção de gene mecA. Ainda, foi realizada a avaliação da produção de lipase de cepas de S. aureus isoladas de animais (úbere e fossas nasais), alimentos (queijo ricota) e de feridas humana infectadas (ambiente hospitalar). Foi observada a produção de lipase nos isolados de feridas humanas (43/50), animais (16/30), queijo (34/41), bancada de preparo de carne (24/24) e bancada de preparo de vegetais (22/24). Todas as cepas isoladas de bancada de corte de carne, vegetais e de queijo produziram protease com zonas de precipitação de diâmetros variando de < 0,5 a 4 mm. Dentre 48 S. aureus isolados de superfícies de processamento de alimentos testados, 100% foram sensíveis a clorafenicol, norfloxacina e meticilina. Doze isolados foram resistentes a eritromicina e tetraciclina, enquanto todos os isolados foram resistentes à estreptomicina e penicilina. Nas reações de amplificação não foi identificado o fragmento correspondente ao gene mecA entre os isolados avaliados. As atividades lipolítica e proteolítica, bem como resistência a antibióticos (mesmo para aqueles já sem valor terapêutico) se constituem em importantes marcadores genéticos e epidemiológicos podendo contribuir para a caracterização de amostras ambiente ou hospedeiro-específicas, bem como, se realizada periodicamente, para se distinguir novas linhagens daquelas endêmicas.

Clostridium difficile is the leading cause of death from gastrointestinal infections in Canada. Current antiobiotic treatment is non-ideal due to the high incidence of relapse and the rise in hyper-virulent antibiotic-resistant strains. Surface layer proteins (SLPs) cover the entire bacterial surface and mediate adherence to host cells. Passive and active immunization against SLPs greatly enhances survival in hamsters, suggesting that antibody-mediated bacterial neutralization may be an effective alternative therapeutic strategy. Using a recombinant-antibody phage display library, and SLPs from strain QCD 32g58 as bait antigen, we isolated and extensively characterized 11 SLP-specific recombinant single-domain antibodies (sdAbs), in terms of affinity and specificity, intrinsic stability, and ability to inhibit cell motility. Several sdAbs exhibit promising characteristics for a potential oral therapeutic based on their high affinity, high thermal stability, and resistance to pepsin digestion. Our study provides the basis of a proof-of-principle model with which to develop specific, broadly neutralizing and intrinsically stable antibodies for the oral therapy of C. difficile infections, as an alternative to conventional antibiotic treatment.

Clostridium difficile is the leading cause of death from gastrointestinal infections in Canada. Current antiobiotic treatment is non-ideal due to the high incidence of relapse and the rise in hyper-virulent antibiotic-resistant strains. Surface layer proteins (SLPs) cover the entire bacterial surface and mediate adherence to host cells. Passive and active immunization against SLPs greatly enhances survival in hamsters, suggesting that antibody-mediated bacterial neutralization may be an effective alternative therapeutic strategy. Using a recombinant-antibody phage display library, and SLPs from strain QCD 32g58 as bait antigen, we isolated and extensively characterized 11 SLP-specific recombinant single-domain antibodies (sdAbs), in terms of affinity and specificity, intrinsic stability, and ability to inhibit cell motility. Several sdAbs exhibit promising characteristics for a potential oral therapeutic based on their high affinity, high thermal stability, and resistance to pepsin digestion. Our study provides the basis of a proof-of-principle model with which to develop specific, broadly neutralizing and intrinsically stable antibodies for the oral therapy of C. difficile infections, as an alternative to conventional antibiotic treatment.

Clostridium difficile is the leading cause of death from gastrointestinal infections in Canada. Current antiobiotic treatment is non-ideal due to the high incidence of relapse and the rise in hyper-virulent antibiotic-resistant strains. Surface layer proteins (SLPs) cover the entire bacterial surface and mediate adherence to host cells. Passive and active immunization against SLPs greatly enhances survival in hamsters, suggesting that antibody-mediated bacterial neutralization may be an effective alternative therapeutic strategy. Using a recombinant-antibody phage display library, and SLPs from strain QCD 32g58 as bait antigen, we isolated and extensively characterized 11 SLP-specific recombinant single-domain antibodies (sdAbs), in terms of affinity and specificity, intrinsic stability, and ability to inhibit cell motility. Several sdAbs exhibit promising characteristics for a potential oral therapeutic based on their high affinity, high thermal stability, and resistance to pepsin digestion. Our study provides the basis of a proof-of-principle model with which to develop specific, broadly neutralizing and intrinsically stable antibodies for the oral therapy of C. difficile infections, as an alternative to conventional antibiotic treatment.