Identification of Lactic Acid Bacteria within the Consortium of a Kefir Grain by Sequencing 16S rDNA Variable Regions
Abstract:The microflora of a kefir grain was identified using a polymerase chain reaction-based strategy combined with 16S rRNA gene sequencing. DNA was extracted from the kefir grain and amplified in its 16S rDNA V1 and V2 regions. To guarantee a good representation of the overall lactic acid bacteria populations, DNA amplification was performed separately with primers specific either to the dominant or to the less abundant bacterial groups. The amplified fragments were cloned in Escherichia coli and then sequenced. Sequences of the V1 region were gathered into 5 groups of similarity and identified by aligning with the sequences of a public library. The V1 region allowed the identification of Lactobacillus kefiranofaciens, L. kefir, L. parakefir, and Lactococcus lactis but was inappropriate for the identification of leuconostocs at species level. Among 16S rDNA variable regions, the V2 region showed the highest variability between Leuconostoc species. Nevertheless, even in the V2 region, differences were too tenuous for effective identification of L. mesenteroides. The methodology described here allowed detection of the dominant species within each targeted microbial group.
Document Type: Research Article
Affiliations: Dpartement Qualit des Productions Agricoles, Centre Wallon de Recherches Agronomiques (CRA-W), 24 Chausse de Namur, B-5030 Gembloux, Belgium.
Publication date: July 1, 2007
More about this publication?
- The Journal of AOAC INTERNATIONAL publishes refereed papers and reviews in the fields of chemical, biological and toxicological analytical chemistry for the purpose of showcasing the most precise, accurate and sensitive methods for analysis of foods, food additives, supplements and contaminants, cosmetics, drugs, toxins, hazardous substances, pesticides, feeds, fertilizers and the environment available at that point in time. The scope of the Journal includes unpublished original research describing new analytical methods, techniques and applications; improved approaches to sampling, both in the field and the laboratory; better methods of preparing samples for analysis; collaborative studies substantiating the performance of a given method; statistical techniques for evaluating data. The Journal will also publish other articles of general interest to its audience, e.g., technical communications; cautionary notes; comments on techniques, apparatus, and reagents.
- Information for Authors
- Submit a Paper
- Subscribe to this Title
- Information for Advertisers
- Journal Information
- ingentaconnect is not responsible for the content or availability of external websites