DETECTION OF TOXIC ESCHERICHIA COLI STRAINS BY PCR TECHNIQUE

Milk products are inhabitant complex system of bacteria. The samples which were obtained from cheese contained 27A, 9F, K12, 22B and 29C strains of bacteria. With the help of biochemical tests like indole, mrvp, Mc. agar, Motility tests identified the type of bacteria that is whether these belong to E. coli or not, and by using the genetic testing with help of Eric primers the different strains of E. coli could be identified, and using the toxic primers like STX, EAE and LT primers the toxic strain of E. coli could be identified by running the samples on gel electrophoresis and comparing the product size length. And finally the toxic strains were identified. All the samples were strains of E. coli bacteria and 22B was the best strain and it had shown high growth and motility. From the gel image of Eric primers, 9F, K12 and 22B are the different strains of E. coli. From the STX toxic primer, K12 and 22B are toxic strains of E. coli. So the samples collected from the soft cheese are all not toxic, only some strains like K12 and 22B are toxic. So the cheese, which has these toxic strains, is harmful to human beings