Identification of a microscopically selected microorganism in milk samples

J Dairy Sci. 2014 Feb;97(2):609-15. doi: 10.3168/jds.2013-6932. Epub 2013 Dec 2.

Abstract

Identification of unwanted microbial contaminants microscopically observed in food products is challenging due to their low abundance in a complex matrix, quite often containing other microorganisms. Therefore, a selective identification method was developed using laser capture microdissection in combination with direct-captured cell PCR. This procedure was validated with Geobacillus stearothermophilus and further used to identify microbial contaminants present in some industrial milk samples. The microscopically observed contaminants were identified as mainly Methylobacterium species.

Keywords: bacterial contamination; cultivation-independent identification; direct-captured cell PCR; laser capture microdissection.

MeSH terms

  • Animals
  • Food Microbiology*
  • Geobacillus stearothermophilus / genetics
  • Geobacillus stearothermophilus / isolation & purification*
  • Laser Capture Microdissection / instrumentation
  • Laser Capture Microdissection / methods*
  • Milk / microbiology*
  • Molecular Sequence Data
  • Polymerase Chain Reaction / instrumentation
  • Polymerase Chain Reaction / methods*
  • RNA, Bacterial / genetics
  • RNA, Bacterial / metabolism
  • RNA, Ribosomal, 16S / genetics
  • RNA, Ribosomal, 16S / metabolism
  • Reproducibility of Results
  • Sequence Analysis, DNA

Substances

  • RNA, Bacterial
  • RNA, Ribosomal, 16S