Exotoxinas estafilocócicas e sua importância na mastite bovina

Abstract

Staphylococcus aureus, belongs to the Staphylococcus gender and is a spherical bacterium of the group of Gram-positive cocci. It can exist as commensal of the human body, integrating the microbiota of the skin, mucous membranes and other anatomical sites. It is considered the major human pathogen, but is also associated with a great variety of animal diseases, recognized worldwide as one of the main pathogens causing mastitis in dairy cows. The microorganism can produce a wide variety of virulence factors secreted or associated with bacterial wall, among them the exotoxins, such as toxic shock syndrome toxin, a bacterial superantigen able to activate the host immune response, the exfoliative toxins A and B, responsible for the clinical manifestations of Staphylococcal scalded skin syndrome, and Panton- Valentine leukocidin, able to produce a pore-form structure in myeloid cells of the host. The pathogenicity of S. aureus to the bovine udder is not quite clarified, but the secreted staphylococcal exotoxins and their combinations may play a role in the pathogenic potential of the microorganism. Considering that knowing the virulence factors of S. aureus provides an important information of the establishment of effective control strategies of intramammary infections we aimed to report the advances of science in relation to major staphylococcal exotoxins.