Expression of superantigens and the agr system in Staphylococcus epidermidis

Autor(es)

Pereira, Valeria Cataneli ^{[1, 2]} ; Pinheiro, Luiza ^[1] ; Oliveira, Adilson ^[1] ; Martins, Katheryne Benini ^[1] ; Moraes Ribolia, Danilo Flavio ^[1] ; Ribeiro de Souza da Cunha, Maria de Lourdes ^[1]

Afiliação do(s) autor(es)

^[1] UNESP Univ Estadual Paulista, Inst Biosci, Dept Microbiol & Immunol, Lab Bacteriol, BR-18618970 Botucatu, SP - Brazil

^[2] Univ Oeste Paulista, BR-19050920 Presidente Prudente, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Microbial Pathogenesis; v. 115, p. 19-24, FEB 2018.
• Citações Web of Science: 2

Resumo

Infections with coagulase-negative staphylococci (CoNS) can involve the production of toxins such as super antigens, which contribute to tissue degradation and inflammatory immune responses. The accessory gene regulator (agr) quorum sensing system coordinates the expression of most S. aureus virulence factors. Therefore, the aim of this study was to investigate the expression of these superantigens and the presence of the agr locus in CoNS strains isolated from blood cultures. PCR was used to detect enterotoxin and agr genes and expression was analyzed by RT-PCR. Expression of the sea gene was observed in one S. epidermidis isolate and of sec-1 in two, seg and sei were expressed concomitantly in one isolate, and sei was expressed in another isolate. The agr group I was detected in S. epidermidis expressing the sea, seg and sei genes, whereas agr group II was detected in isolates expressing thesec-1 gene. The agr groups were only expressed in strains expressing thesec-1 gene. The results show that enterotoxin genes are highly frequent in CoNS isolated from clinical specimens and confirm the toxin producing ability of these strains. The agr group II may be associated with enterotoxin C production by S. epidermidis, increasing the virulence of strains isolated from blood cultures and consequently the severity of sepsis caused by these organisms. (AU)

• Processo FAPESP: 11/23746-2 - Evidência da presença do sistema AGR, expressão de toxinas e resistência aos antimicrobianos em estafilococos coagulase-negativa isolados de hemoculturas
• Beneficiário: Valéria Cataneli Pereira
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto