Quantificação e identificação genotípica do gene COA de staphylococcus aureus a partir de queijos e embutidos

Abstract

Among the various types of pathogenic microorganisms that can be transmitted through milk and dairy products and pork, there are Staphylococcus aureus, whose importance in the epidemiology of foodborne diseases stems from its high prevalence and the risk of production of toxins in contaminated food that cause gastroenteritis food. S. aureus are gram-positive cocci, seen under the microscope in the disposition of grape clusters or in pairs, mesophilic, aerobic or facultative anaerobes. Staphylococcal enterotoxins have high thermal resistance and can survive heat treatments applied in foods, such as pasteurization. The technique of Polymerase Chain Reaction amplification is based on DNA and has been shown to be useful for identifying the source S. aureus in food differentiating strains from human and animal infections, because it is seen as a technique extremely reliable, reproducible, rapid and highly discriminatory. S. aureus’ population has shown considerable variability in genomic content. This variability contributes to the emergence of different epidemiological profiles that are dependent strains / isolates, suggesting the need to identify these subtypes before applying specific measures to control this bacteria. The aim of this work was to isolate Staphylococcus aureus in cheese and sausages. The technique used, known by PCR recreates large amount of a gene from a tiny fraction of DNA. Demonstrates advantages such as reduced time laboratory reducing the number of reagents, among others. This study verified the presence of Staphylococcus sp 100% of embedded samples and 75% of the samples of cheese. However, the application of PCR, obtained as a result of a dispute regarding ace colonies that were positive for coagulase test and the presence of the coa gene, thus demonstrating that the biochemical test is not completely accurate.