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. 2006 Feb;72(2):1702-4.
doi: 10.1128/AEM.72.2.1702-1704.2006.

Freezing induces biased results in the molecular detection of Flavobacterium columnare

Lotta-Riina Suomalainen  1 , Hilkka Reunanen, Ritva Ijäs, E Tellervo Valtonen, Marja Tiirola
Affiliations

Freezing induces biased results in the molecular detection of Flavobacterium columnare

Lotta-Riina Suomalainen et al. Appl Environ Microbiol. 2006 Feb.

Abstract

Specific PCR detection and electron microscopy of Flavobacterium columnare revealed the risk of false-negative results in molecular detection of this fish pathogen. Freezing and thawing destroyed the cells so that DNA was for the most part undetectable by PCR. The detection of bacteria was also weakened after prolonged enrichment cultivation of samples from infected fish.

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Figures

FIG. 1.
FIG. 1.
Effect of incubation time on PCR detection of F. columnare enriched from skin samples of infected fish (lanes A and B) and from tank water (lanes W). The numbers indicate the time of enrichment in Shieh medium (in days). f indicates that a sample was frozen between enrichment and DNA extraction. Lane λ/HE consists of a lambda/HindIII-EcoRI size ladder. Lane + contained a PCR positive control, and lane − contained a PCR negative control.
FIG. 2.
FIG. 2.
Effect of sample freezing on PCR detection of F. columnare from infected fish skin. Samples (lanes A to I) were enriched for 3 days in Shieh medium prior to analysis. f indicates that a sample was frozen between enrichment and DNA extraction. Lane λ/HE consists of a lambda/HindIII-Eco-RI size ladder. Lane + contained a PCR positive control, and lane − contained a PCR negative control.
FIG. 3.
FIG. 3.
F. columnare HTAN5/03 cells observed by electron microscopy. (A) Cells observed after 7 days of cultivation. (B) Frozen cells observed after 3 days of cultivation and sample freezing. (C) Cells observed after 3 days of cultivation. The arrows indicate visible spheroplasts.
See this image and copyright information in PMC

References

    1. Bader, J. A., C. A. Shoemaker, and P. H. Klesius. 2003. Rapid detection of columnaris disease in channel catfish (Ictalurus punctatus) with a new species-specific 16-S rRNA gene-based primer for Flavobacterium columnare. J. Microbiol. Methods 52:209-220. - PubMed
    1. Bernardet, J.-F., and P. A. D. Grimont. 1989. Deoxyribunucleic acid relatedness and phenotypic characterization of Flexibacter columnaris sp. nov., nom. rev., Flexibacter pschrophilus sp. nov., nom. rev., and Flexibacter maritimus Wakabayashi, Hikida and Masumura 1996. Int. J. Syst. Bacteriol. 39:346-354.
    1. Bertolini, J. M., and J. S. Rohovec. 1992. Electrophoretic detection of proteases from different Flexibacter columnaris strains and assessment of their variability. Dis. Aquat. Org. 12:121-128.
    1. Brinkman, J. A., M. Z. Rahmani, W. E. Jones, A. K. Chaturvendi, and M. E. Hagensee. 2004. Optimization of PCR based detection of human papillomavirus DNA from urine specimens. J. Clin. Virol. 29:230-240. - PubMed
    1. Decostere, A., F. Haesebrouck, and L. A. Devriese. 1997. Shieh medium supplemented with tobramycin for selective isolation of Flavobacterium columnare (Flexibacter columnaris) from diseased fish. J. Clin. Microbiol. 35:322-324. - PMC - PubMed

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