Large-scale metagenomic sequence clustering on map-reduce clusters.

J Bioinform Comput Biol
Authors
Keywords
Abstract

Taxonomic clustering of species from millions of DNA fragments sequenced from their genomes is an important and frequently arising problem in metagenomics. In this paper, we present a parallel algorithm for taxonomic clustering of large metagenomic samples with support for overlapping clusters. We develop sketching techniques, akin to those created for web document clustering, to deduce significant similarities between pairs of sequences without resorting to expensive all vs. all comparison. We formulate the metagenomic classification problem as that of maximal quasi-clique enumeration in the resulting similarity graph, at multiple levels of the hierarchy as prescribed by different similarity thresholds. We cast execution of the underlying algorithmic steps as applications of the map-reduce framework to achieve a cloud ready implementation. We show that the resulting framework can produce high quality clustering of metagenomic samples consisting of millions of reads, in reasonable time limits, when executed on a modest size cluster.

Year of Publication
2013
Journal
J Bioinform Comput Biol
Volume
11
Issue
1
Pages
1340001
Date Published
2013 Feb
ISSN
1757-6334
URL
DOI
10.1142/S0219720013400015
PubMed ID
23427983
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