Phylogenetic Tree of Gene Enterotoxin B in Staphylococcus aureus Isolated from Dairy Products and Human Stool

Abstract

Collected 280samples from two different sources, which included samples from dairy products and stool samples for intestinal infection patients suspected of suffering from food poisoning according to the diagnosis of the specialist doctor, distributed on 200 samples of stool samples from patients, and the other source of samples included 80 dairy products. For the period from 1/12/2019 to 1/10/2020.For the isolation of Staphylococcus aureus and to detect the seb gene and characterize from a genetic and phylogeny, the results showed that the Staph. aureus bacteria found in 15 isolates with 20.83% of the dairy product samples, while it was found that it recorded an isolation rate of 9.03% of the total of stool samples from patients.Enterotoxin SEB was detected in Staph.aureus bacteria and in both sources (dairy products and stool samples) through the use of (PCR) technique. It was proved that the seb gene is present in Staph.aureus bacteria, as the presence of the seb gene was shown at a rate of 33% and 40% for each isolates of the dairy products and stool samples respectively, then analyzed the genetic tree of the seb gene encoding for the production of enterotoxin SEB by means of the Mega X program, and the results of the genetic tree analysis showed a clear genetic variation and mutations with global Staph.aureus isolates, as our isolates taken from Stool samples of the patients and dairy products in the NCBI Database) and accession numbers were given in the GenBank.