ARK: Aggregation of Reads by K-Means for Estimation of Bacterial Community Composition
2015 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 10, no 10, e0140644Article in journal (Refereed) Published
Motivation Estimation of bacterial community composition from high-throughput sequenced 16S rRNA gene amplicons is a key task in microbial ecology. Since the sequence data from each sample typically consist of a large number of reads and are adversely impacted by different levels of biological and technical noise, accurate analysis of such large datasets is challenging. Results There has been a recent surge of interest in using compressed sensing inspired and convex-optimization based methods to solve the estimation problem for bacterial community composition. These methods typically rely on summarizing the sequence data by frequencies of low-order k-mers and matching this information statistically with a taxonomically structured database. Here we show that the accuracy of the resulting community composition estimates can be substantially improved by aggregating the reads from a sample with an unsupervised machine learning approach prior to the estimation phase. The aggregation of reads is a pre-processing approach where we use a standard K-means clustering algorithm that partitions a large set of reads into subsets with reasonable computational cost to provide several vectors of first order statistics instead of only single statistical summarization in terms of k-mer frequencies. The output of the clustering is then processed further to obtain the final estimate for each sample. The resulting method is called Aggregation of Reads by K-means (ARK), and it is based on a statistical argument via mixture density formulation. ARK is found to improve the fidelity and robustness of several recently introduced methods, with only a modest increase in computational complexity. Availability An open source, platform-independent implementation of the method in the Julia programming language is freely available at https://github.com/dkoslicki/ARK. A Matlab implementation is available at http://www.ee.kth.se/ctsoftware.
Place, publisher, year, edition, pages
PUBLIC LIBRARY SCIENCE , 2015. Vol. 10, no 10, e0140644
Split Vector Quantization, LSF Parameters, Sequences, Megan
IdentifiersURN: urn:nbn:se:kth:diva-176956DOI: 10.1371/journal.pone.0140644ISI: 000363309200025PubMedID: 26496191ScopusID: 2-s2.0-84949460421OAI: oai:DiVA.org:kth-176956DiVA: diva2:883073
QC 201512162015-12-162015-11-132015-12-16Bibliographically approved