title: Molecular screening of staphylococcal enterotoxin B gene in clinical isolates.
abstract: OBJECTIVE
  The role of staphylococcal enterotoxin B (SEB) in food poisoning is well known, however its role in other diseases remains to be explored. The aim of this study is the molecular screening and characterization of the SEB gene in clinically isolated strains.
  
  
  METHODS
  In this experimentally study, 300 Staphylococcus aureus (S. aureus) strains isolated from clinical samples were assayed. The isolated strains were confirmed by conventional bacteriological methods. Polymerase chain reaction (PCR) was used to determine the enterotoxin B (ent B) gene. Assessment of toxin production in all strains that contained the ent B gene was then performed. Finally, using specific antibody against SEB, a Western-blot was applied to confirm detection of enterotoxin B production.
  
  
  RESULTS
  RESULTS indicated that only 5% of the 300 clinically isolated S. aureus contained the ent B gene. All strains which contained the ent B gene produced a proteinous enterotoxin B. The results of sequence determination of the PCR product were compared with the gene bank database and 98% similarity was achieved. The results of the Western-blot confirmed that enterotoxin B was produced in strains that contained the ent B gene.
  
  
  CONCLUSIONS
  The results of this study indicate that 5% of clinically isolated S. aureus strains produce enterotoxin B. Considering that the enterotoxin B is an important superantigen, it is possible that a delay in diagnosis and lack of early proper treatment can cause an incidence of late complications, particularly in staphylococcal chronic infections. For this reason, it is suggested that in addition to detecting bacteria, an enterotoxin B detection test should be performed to control its toxigenicity.
authors.affiliation: 1:Department of Medical Microbiology, Therapeutic Microbial Toxin Research Center, Faculty of Medicine, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Ramezan Ali
authors.initials: RA
authors.lastname: Ataee
authors.forename: Ali
authors.initials: A
authors.lastname: Karami
authors.forename: Morteza
authors.initials: M
authors.lastname: Izadi
authors.forename: Aref
authors.initials: A
authors.lastname: Aghania
authors.forename: Mohammad Hossein
authors.initials: MH
authors.lastname: Ataee
keywords: Enterotoxin B; PCR; Screening; Staphylococcus aureus; Western-Blot