Sequences and their use for detection and characterization of

1. A method for detecting the presence of E. coli 0157:H7 in a sample, said sample comprising nucleic acids, said method comprising:

(a) providing a reaction mixture comprising suitable primer pairs for amplification of at least portions of

(i) two or more regions of p0157 of the E. coli 0157:H7 genome, wherein said primer pairs are suitable for amplification of SEQ ID NO: 2 and SEQ ID NO: 3, wherein said primer pair for amplification of the nucleic acid region of SEQ ID NO: 2 comprises SEQ ID NO: 12 and SEQ ID NO: 13, wherein said primer pair for amplification of the nucleic acid region of SEQ ID NO: 3 comprises SEQ ID NO:16 and SEQ ID NO:17, and

(ii) one or more E. coli 0157:H7 genomic DNA regions outside the p0157 portion of the E. coli 0157:H7 genome, wherein said primer pair is suitable for amplification of SEQ ID NO: 1, and wherein said primer pair for amplification of SEQ ID NO: 1 comprises SEQ ID NO:5 and SEQ ID NO:6;

(b) performing PCR amplification of said nucleic acids of said sample using the reaction mixture of step (a); and

(c) detecting the amplification of step (b), whereby a positive detection of amplification in (a)(i) and (a)(ii) indicates the presence of E. coli 0157:H7 in the sample.

2. The method of claim 1 , wherein said reaction mixture further comprises one nucleic acid probe for each nucleic acid region selected.

3. The method of claim 2 , wherein said nucleic acid probes comprise one or more of SEQ ID NO:7, SEQ ID NO:14, and SEQ ID NO:18.

4. The method of claim 1 , wherein the sample comprises a food sample or a water sample.