This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Picard, F. J.
Right arrow Articles by Bergeron, M. G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Picard, F. J.
Right arrow Articles by Bergeron, M. G.

 Previous Article  |  Next Article 

Journal of Clinical Microbiology, March 2009, p. 751-757, Vol. 47, No. 3
0095-1137/09/$08.00+0     doi:10.1128/JCM.01746-08
Copyright © 2009, American Society for Microbiology. All Rights Reserved.

Internal Control for Nucleic Acid Testing Based on the Use of Purified Bacillus atrophaeus subsp. globigii Spores{triangledown}

François J. Picard,1,2 Martin Gagnon,1 Marthe R. Bernier,1 Nicholas J. Parham,1 Martine Bastien,1 Maurice Boissinot,1,2 Régis Peytavi,1,2 and Michel G. Bergeron1,2*

Centre de Recherche en Infectiologie de l'Université Laval, Centre Hospitalier Universitaire de Québec (Pavillon CHUL), Québec, Québec, Canada,1 Division de Microbiologie, Faculté de Médecine, Université Laval, Québec, Québec, Canada2

Received 9 September 2008/ Returned for modification 10 October 2008/ Accepted 27 November 2008

Commonly used internal controls (ICs) to monitor the efficiency of nucleic acid testing (NAT) assays do not allow verification of nucleic acid extraction efficiency. Since microbial cells are often difficult to lyse, it is important to ensure that nucleic acids are efficiently extracted from any target organism. For this purpose, we developed a cellular IC based on the use of nonpathogenic Bacillus spores. Purified Bacillus atrophaeus subsp. globigii (referred to hereafter as simply B. atrophaeus) spores were added to vaginal and anal samples, which were then subjected to rapid DNA extraction and subsequent PCR amplification. The proof of concept of this cellular IC was made through the use of both manual and automated DNA extraction methods, using vaginal or anal samples spiked with B. atrophaeus spores, combined with a multiplex real-time PCR assay for the specific detection of group B streptococci (GBS) and B. atrophaeus. The performance of the cellular IC was compared to that of a standard IC plasmid added to PCRs. Approximately 500 B. atrophaeus spores per PCR was found to be optimal since this did not interfere significantly with GBS detection for either DNA extraction method and yielded reproducible amplification and/or detection of B. atrophaeus genomic DNA serving as an IC template. Performance of the cellular IC was comparable to that of the standard IC. This novel IC system using nonpathogenic and hard-to-lyse B. atrophaeus spores allowed validation of both the DNA extraction procedure and the amplification and detection process. Use of a spore-based control also provides a universal control for microbial cell lysis.

* Corresponding author. Mailing address: Centre de Recherche en Infectiologie de l'Université Laval, Centre Hospitalier Universitaire de Québec, Pavillon CHUL, 2705 Laurier Blvd., Québec, Québec G1V 4G2, Canada. Phone: (418) 654-2705. Fax: (418) 654-2715. E-mail: michel.g.bergeron{at}crchul.ulaval.ca

{triangledown} Published ahead of print on 14 January 2009.

Journal of Clinical Microbiology, March 2009, p. 751-757, Vol. 47, No. 3
0095-1137/09/$08.00+0     doi:10.1128/JCM.01746-08
Copyright © 2009, American Society for Microbiology. All Rights Reserved.





Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»