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The present study was carried out for the assessment and detecting of the Escherichia coli and Staphylococcus aureus bacteriophages and their bacterial host's proteins includes visual inspection and comparison of their molecular weight mass. Systematic methods that use microorganisms (viruses and bacteria) to test samples from the local sewage water have been developed but require some change in the classical culturing of the organism to detect it easily by naked eye through the changes in selective media. We have developed a Sodium Dodecyl Sulphate Ploy Acrylamide Gel Electrophoresis (SDS PAGE) assay for bacteriophage samples preparation that allows the rapid detection of proteins bands of these viruses by using freeze drying technique. We found that the protein profiles of E. coli bacteriophage showed three major bands with molecular weight mass of 47, 35 and 16 kilo Dalton and 34 and 20 kDa for S. aureus phage, the band of 35 kDa was the common shared peak between the phage and the bacterial host due to the bacteriophage lytic cycle. The method is suitable for use with both the bacteriophages and their bacterial hosts. The assay is rapid, sensitive, and inexpensive; requires only small sample volumes; and can be automated.

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Vegetables can be vehicles for transmission of E. coli O157:H7 to humans, therefore, this study carried out in order to investigate the presence of Enterohemorrhagic E. coli in ten different types of leafy green vegetables, determined their susceptibility to thirteen antibiotics and detected the presence of some virulence genes. Method: Five-hundred samples of green leafy vegetables namely (Lettuce, Spanish, Rocket, Parsley, Mallow, Coriander, Portulaca, Lettuce, Dill, Basil and Chard) were examined for presence of E. coli O157:H7, by using standard microbiological tests (CHROMagarTM O157:H7), further detection of E. coli O157:H7 was done by Multiplex PCR (mPCR) for the detection of virulence genes (stx1, stx2, intmin and hlyA) These genes are causative factors of settlement, adhesion, and attack of STEC bacteria to gastrointestinal mucosa. Results: E. coli O157:H7 was isolated from eight (80%) out of ten types of green leafy vegetable as 12 (2.40%) in which the highest percentage of isolation was shown in Dill and Chards samples as (4.2%), Coriander and Mallow showed percentage of isolation as (3.33% and 3.03%) respectively, Parsley, Portulaca and Lettuce showed percentages of isolation as 2.43%, 1.92%, respectively, the least percentage of isolation was shown in Rocket (1.7%), No E. coli O157:H7, was detected in Spinach and Basil. Makkah collected samples showed isolation of 7 isolates out of 12 (58.33%). All isolates were resistant to Methicillin (5µg), Metronidazole (5 µg) and Ampicillin (10 µg). Stx2 (110 bp), Stx1 (349 bp), hly A (165 bp) genes were detected. All isolates showed negative results for presence of intimin gene (890 bp). This study concluded that there is a high risk for occurrence of E. coli O157:H7 outbreaks due to consumption of the green leafy vegetables sold in Jeddah Central Market.