Study on the Molecular Characteristics of Superantigen in Staphylococcus aureus Isolated from Different Groups of People

Objective To explore the molecular characteristics of superantigen in Staphylococcus aureus isolated from blood of patients with bacterial sepsis,anterior nasal cavities of heath care workers,hospitalized patients with non-infective diseases and healthy people from communities.Methods A total of 277 Staphylococcus aureus strains were tested for presence of genes encoding staphylococcal enterotoxin(SE)and toxic shock syndrome toxin-1(TSST-1) by PCR and multiplex PCR.Results SE gene(se) was detected in 51%(142/277) strains.The positive rate of se in isolates from people in hospital(50%-59%) was significantly higher than that in isolates from people in community(36%)(P0.05).The se in isolates from people in hospital was mainly A type,while that from healthy people in community was mainly D type.The positive rate of tsst-1 gene in isolates from blood of patients with bacterial sepsis was significantly higher than that in isolates from other groups(P0.01).Conclusions The superantigen genes of Staphylococcus aureus isolated from different sources of people have different characteristics.This finding is important for clinical diagnosis,treatment and epidemiological study of Staphylococcus aureus.