title: Enterotoxin gene profile of Staphylococcus aureus isolates recovered from bovine milk produced in central Ethiopia.
abstract: BACKGROUND
  Staphylococcal food intoxication is dependent on the production of enterotoxins, the single most important virulence factors. Various studies conducted in Ethiopia have depicted the prevalence of S. aureus in bovine milk. However, there is no published data regarding the enterotoxin gene profile of S. aureus isolates in Ethiopia. The aim of this study was, therefore, to evaluate enterotoxin gene carriage profile of S. aureus isolates recovered from bovine milk samples from central Ethiopia.
  
  
  METHODS
  In this study, 109 S. aureus isolates recovered from bovine milk were analyzed for carriage of the classical enterotoxin genes. Genomic DNA extraction was performed using a commercially available kit. Two sets of multiplex polymerase chain reaction (PCR) assays were used to detect the five classical enterotoxin-coding genes and the toxic shock syndrome toxin gene.
  
  
  RESULTS
  At least one type of S. aureus enterotoxin gene (SE) was carried in 73 (66.9%) of the isolates. The most frequently encountered gene was sea (40; 36.7%) followed by seb (19; 17.4%), see (18; 16.5%), tst (16; 14.7%), sec-1 (12; 11.01%), and sed (7; 6.4%). Of the 73 S. aureus isolates harboring at least one of the enterotoxin genes, 26 (35.6%) strains harbored more than one enterotoxin gene.
  
  
  CONCLUSIONS
  More than half of the S. aureus isolates harbored at least one of the enterotoxin coding genes, indicating milk specimens contaminated by S. aureus could have a high chance of causing food intoxication.
authors.affiliation: Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia. eyasutigabu@ymail.com.
authors.forename: Eyasu Tigabu
authors.initials: ET
authors.lastname: Seyoum
authors.forename: Tesfu Kassa
authors.initials: TK
authors.lastname: Mekonene
authors.forename: Daniel Asrat
authors.initials: DA
authors.lastname: Woldetsadik
authors.forename: Bayleyegn Molla
authors.initials: BM
authors.lastname: Zewudie
authors.forename: Wondwossen Abebe
authors.initials: WA
authors.lastname: Gebreyes
mesh_terms: D000818:Animals; D002417:Cattle; D004269:DNA, Bacterial / Q000235:genetics; D004768:Enterotoxins / Q000235:genetics*; D005002:Ethiopia; D005798:Genes, Bacterial; D005838:Genotype; D008892:Milk / Q000382:microbiology*; D060885:Multiplex Polymerase Chain Reaction; D013211:Staphylococcus aureus / Q000235:genetics* / Q000302:isolation & purification*
chemical_list: D004269:DNA, Bacterial; D004768:Enterotoxins