Distribution of food-borne Staphylococcus aureus enterotoxin genes

Abstract

ABSTRACT. We identified and analyzed 5 new-type enterotoxin genes, including SEj, SEl, SEq, SEm, and SEr, to explore the distribution of 5 enterotoxin genes in Staphylococcus aureus of different origins as well as their correlations and differences. We examined the distribution of the S. aureus enterotoxin genes and their pathogenic mechanisms. A total of 660 specimens were collected from January 2011 to December 2014, and 217 strains of S. aureus were isolated. The template DNA of S. aureus was extracted. The Primer6.0 and Oligo7 software were used to design and synthesize polymerase chain reaction primers. Amplification results were analyzed by electrophoresis, and the amplification products were recovered and sequenced. Thirty-six bacterial strains contained the SEj gene (16.6%), including 15, 8, 8, 4, and 1 strains in fresh meat, quickfrozen food, raw milk, human purulent tissue, and living environment, respectively. Thirty-one bacterial strains contained the SEr gene (14.3%), including 16, 9, and 6 strains in fresh meat, quick-frozen food, and raw milk, respectively. Twenty-one bacterial strains contained the enterotoxin SEq gene (9.7%), including 8, 6, 6, and 1 strains in fresh meat, quickfrozen food, raw milk, and human purulent tissue, respectively. No SEm and SEl genes were detected. Different types of foods carry different types of enterotoxins, providing a basis for quick tracing for food poisoning. Three enterotoxin genes, SEj, SEr, and SEq, showed the highest carrier rate in quick-frozen food. It is imperative to improve their detection in quick-frozen food.

Towards understanding the antagonistic activity of phytic acid against common foodborne bacterial pathogens using a general linear model

“…Another bacterium, S. aureus, which belongs to the Gram-positive Micrococcaceae family, is considered to be one of the most common causes of foodborne disease in the world [10]. This bacterium causes gastrointestinal illness by secreting a range of toxins, including staphylococcal enterotoxins [10][11][12]. S. aureus is also able to form biofilms on food-contact surfaces, which highly increases its stress tolerance and, thus, its persistence in food-related environments [13][14][15][16].…”

The Occurrence and Characteristics of Methicillin-Resistant Staphylococcal Isolates from Foods and Containers

“…Hu et al showed five new types of enterotoxin genes, namely SEj, SEl, SEq, SEm, and SEr. Of these, SEj and SEr were detected in 16.6% and 14.3%, respectively [ 65 ]. Additionally, SEi (97.2%) and SEm (86.1%) were frequently detected in retail foods in China [ 11 ].…”

“…In addition, the five new enterotoxin genes were extensively present in proteins of animal origin compared with that from other origins. This is related to the animal characteristics and interaction with the living environment, operation environment for food processing, and storage environment for finished products [ 65 ].…”

iTRAQ-Based Quantitative Proteomic Analysis Reveals Cold Responsive Proteins Involved in Leaf Senescence in Upland Cotton (Gossypium hirsutum L.)

“…The data were processed using the 2 −ΔΔ C t method, and GhActin and NS Stage 1 were used as internal controls. All of the primer pairs ( Table S9 ) used for qPCR were designed using Oligo 7 [ 67 ].…”