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Quantitative detection of Clostridium tyrobutyricum in milk by real-time PCR.

ABSTRACT: We developed a real-time PCR assay for the quantitative detection of Clostridium tyrobutyricum, which has been identified as the major causal agent of late blowing in cheese. The assay was 100% specific, with an analytical sensitivity of 1 genome equivalent in 40% of the reactions. The quantification was linear (R(2) > 0.9995) over a 5-log dynamic range, down to 10 genome equivalents, with a PCR efficiency of >0.946. With optimized detergent treatment and enzymatic pretreatment of the sample before centrifugation and nucleic acid extraction, the assay counted down to 300 C. tyrobutyricum spores, with a relative accuracy of 82.98 to 107.68, and detected as few as 25 spores in 25 ml of artificially contaminated raw or ultrahigh-temperature-treated whole milk.

SUBMITTER: Lopez-Enriquez L

PROVIDER: S-EPMC1932699 | biostudies-literature | 2007 Jun

REPOSITORIES: biostudies-literature

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Quantitative detection of Clostridium tyrobutyricum in milk by real-time PCR.

López-Enríquez Lorena L Rodríguez-Lázaro David D Hernández Marta M

Applied and environmental microbiology 20070420 11

We developed a real-time PCR assay for the quantitative detection of Clostridium tyrobutyricum, which has been identified as the major causal agent of late blowing in cheese. The assay was 100% specific, with an analytical sensitivity of 1 genome equivalent in 40% of the reactions. The quantification was linear (R(2) > 0.9995) over a 5-log dynamic range, down to 10 genome equivalents, with a PCR efficiency of >0.946. With optimized detergent treatment and enzymatic pretreatment of the sample bef ...[more]

PMID: 17449705

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