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DNA Fingerprinting of Mycobacterium leprae Strains Using Variable Number Tandem Repeat (VNTR) - Fragment Length Analysis (FLA)
Published on: July 15, 2011
Intragenic tandem repeat variation between Legionella pneumophila strains
David A Coil1, Liesbeth Vandersmissen, Christophe Ginevra
1Laboratory of Bacteriology, Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium.
BMC Microbiology
|December 17, 2008
Summary
Intragenic tandem repeats in Legionella pneumophila vary in copy number, potentially influencing bacterial adaptation and virulence. This study reveals distinct repeat patterns linked to environmental and clinical origins.
Area of Science:
- Microbiology
- Genomics
- Evolutionary Biology
Background:
- Bacterial genomes contain numerous tandem repeats, with intragenic repeats' phenotypic effects under investigation.
- Evidence suggests repeats influence gene evolution, regulation, adaptation, and immune evasion in other organisms.
Purpose of the Study:
- To investigate the presence and copy number variability of intragenic tandem repeats in Legionella pneumophila.
- To determine if repeat copy number patterns differ between environmental and clinical isolates.
Main Methods:
- Identified 26 intragenic tandem repeat sequences in the Legionella pneumophila Philadelphia strain.
- Analyzed copy number polymorphism of these repeats across numerous L. pneumophila serogroup 1 strains from diverse origins.
Main Results:
- Seven intragenic tandem repeats showed copy number polymorphism among L. pneumophila strains.
- Six of these seven polymorphic repeats exhibited statistically significant differences in copy number between environmental, clinical, and hot spring origins.
Conclusions:
- Intragenic tandem repeats may contribute to Legionella pneumophila's virulence and environmental adaptation.
- This study is the first to link tandem repeat distribution differences to the clinical or environmental origin of L. pneumophila.
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