×

Method for detection and multiple, simultaneous quantification of pathogens by means of real-time polymerase chain reaction

  • US 8,206,923 B2
  • Filed: 04/19/2007
  • Issued: 06/26/2012
  • Est. Priority Date: 04/24/2006
  • Status: Expired due to Fees
First Claim
Patent Images

1. A method for detecting Listeria spp, Staphylococcus aureus, Campylobacter jejuni, and Escherichia coli O157:

  • H7 in a food or environment sample, the method comprising the steps of;

    a) extracting DNA present in said food or environment sample;

    b) preparing a reaction mixture including said extracted DNA of said food or environment sample, a first pair of oligonucleotide primers consisting of an upstream primer of SEQ ID NO;

    1 and a downstream primer of SEQ ID NO;

    2, which anneals to a first target nucleic acid sequence of Listeria spp, a second pair of oligonucleotide primers consisting of an upstream primer of SEQ ID NO;

    4 and a downstream primer of SEQ ID NO;

    5, which anneals to a second target nucleic acid sequence of Staphylococcus aureus, a third pair of oligonucleotide primers consisting of an upstream primer of SEQ ID NO;

    7 and a downstream primer of SEQ ID NO;

    8, which anneals to a third target nucleic acid sequence of Campylobacter jejuni, a fourth pair of oligonucleotide primers consisting of an upstream primer of SEQ ID NO;

    10 and a downstream primer of SEQ ID NO;

    11, which anneals to a fourth target nucleic acid sequence of Escherichia coli O157;

    H7, a probe consisting of SEQ ID NO;

    3 which is complementary to a sequence within the first target nucleic acid sequence of Listeria sp and is marked at its 5′

    end with TET and at its 3′

    end with BHQ-1, a probe consisting of SEQ ID NO;

    6 which is complementary to a sequence within the second target nucleic acid sequence of Staphylococcus aureus and is marked at its 5′

    end with T×

    R and at its 3′

    end with BHQ-2, a probe consisting of SEQ ID NO;

    9 which is complementary to a sequence within the third target nucleic acid sequence of Campylobacter jejuni and is marked at its 5′

    end with Cy5 and at its 3′

    end with BHQ-3, a probe consisting of SEQ ID NO;

    12 which is complementary to a sequence within the fourth target nucleic acid sequence of Escherichia coli O157;

    H7 and is marked at its 5′

    end with FAM and at its 3′

    end with BHQ-1, and four deoxynucleotide triphosphates (dNTPs) selected from the group consisting of adenosine deoxynucleotide triphosphate (dATP), guanosine deoxynucleotide triphosphate (dGTP), thymidine deoxynucleotide triphosphate (dTTP), cytosine deoxynucleotide triphosphate (dCTP), and nucleotide analogs thereof;

    c) providing a thermostable DNA polymerase and a magnesium salt;

    d) amplifying by multiplex amplification reaction using real-time polymerase chain reaction (PCR), the first target nucleic acid sequence of Listeria spp, the second target nucleic acid sequence of Staphylococcus aureus, the third target nucleic acid sequence of Campylobacter jejuni, and the fourth target nucleic acid sequence of Escherichia coli O157;

    H7 from the extracted DNA of pathogens of said food or environment sample in the reaction mixture under suitable PCR reaction mixture temperature conditions by a repetitive series of PCR cycling steps by annealing the oligonucleotide primers of the step (b) to the extracted DNA and extending the annealed the oligonucleotide primers with the four deoxynucleotide triphosphates (dNTPs), the DNA polymerase and the magnesium salt, to provide amplified PCR products; and

    e) following amplification, determining the presence or absence of the first, second, third and fourth target nucleic acids in the amplified PCR products by means of a fluorescent signal or fluorescence emission specific for each target nucleic acid; and

    wherein the Listeria spp, Staphylococcus aureus, Campylobacter jejuni and Escherichia coli O157;

    H7 are simultaneously detected and quantified in said food or environment sample.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×