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A Microscopic Phenotypic Assay for the Quantification of Intracellular Mycobacteria Adapted for High-throughput/High-content Screening
Published on: January 17, 2014
Using affinity propagation for identifying subspecies among clonal organisms: lessons from M. tuberculosis
Claudio Borile1, Mathieu Labarre, Silvio Franz
1LPTMS, CNRS and Univ. Paris-Sud, UMR8626, Bat. 100, 91405 Orsay, France.
BMC Bioinformatics
|June 4, 2011
Summary
This study refines the classification of Mycobacterium tuberculosis complex strains using Affinity Propagation, improving the understanding of the "Euro-American" lineage and its T family. The new method offers better strain categorization for tuberculosis research.
Area of Science:
- Microbiology and Evolutionary Biology
- Bioinformatics and Computational Biology
- Genetics and Genomics
Background:
- Accurate classification of clonal organisms like Mycobacterium tuberculosis complex (MTC) is crucial for understanding and managing diseases such as tuberculosis (TB).
- Existing classification methods for MTC, particularly spoligotyping, face challenges in defining clear boundaries for certain lineages, such as the T family.
- The T family and its T1 subfamily within the
- Euro-American
- lineage are known to be non-monophyletic, necessitating refined classification strategies.
Purpose of the Study:
- To apply the Affinity Propagation clustering algorithm to identify patterns within the CRISPR locus of MTC strains.
- To refine the classification of MTC strains, particularly within the
- Euro-American
- lineage and its T family.
- To develop a more robust method for inferring evolutionary relationships and divergence times between MTC strains.
Main Methods:
- Utilized the Affinity Propagation clustering algorithm, a method previously successful in image categorization, for analyzing MTC CRISPR locus patterns.
- Employed a distance method inspired by evolutionary models to infer divergence times, comparing its efficacy against the Jaccard index.
- Applied Affinity Propagation to the SpolDB4 international spoligotyping database to reassess and propose consensus assignments for existing spoligotypes.
Main Results:
- Affinity Propagation effectively identified relevant patterns at the CRISPR locus in MTC.
- The proposed distance method demonstrated superior performance compared to the Jaccard index for comparing spoligotype patterns.
- A consensus assignation for all SpolDB4 spoligotypes was proposed, and new signatures were identified to subclassify the T family.
Conclusions:
- Affinity Propagation serves as a valuable tool for building and refining classifications of clonal organisms.
- The study established well-supported families and subfamilies within the MTC, with a particular focus on enhancing the classification of the
- Euro-American
- lineage.
- The refined classification provides a better framework for understanding the evolutionary dynamics and epidemiology of tuberculosis.
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