Pathoscope

Pathoscope performs strain-level read assignment and quantification of microbial strains from metagenomic next-generation sequencing data.

Key Features:

• Complete metagenomic analysis framework: Implements reference genome library extraction and indexing, read quality control and alignment, strain identification, and result summarization and annotation.
• Bayesian read reassignment: Propagates evidence within a Bayesian framework and uses an expectation-maximization algorithm to reassign mapping membership based on initial alignment results, enhancing specificity for strain identification.
• High sensitivity and efficiency: Evaluated on simulated data and real-world datasets, including the 2011 Shiga-toxigenic Escherichia coli O104:H4 outbreak, demonstrating superior sensitivity, efficiency, scope, speed, and accuracy relative to alternative approaches.
• Strain-level quantification: Rapidly and accurately quantifies the proportions of reads originating from individual microbial strains within complex datasets.

Scientific Applications:

• Microbial ecology: Resolves community composition and strain-level diversity in environmental microbiome studies.
• Clinical pathogen detection: Identifies and quantifies pathogenic organisms in clinical metagenomic samples for human health investigations.
• Outbreak investigation: Analyzes metagenomic datasets from outbreak scenarios, as exemplified by the 2011 E. coli O104:H4 outbreak evaluation.

Methodology:

Computational steps include reference genome library extraction and indexing, read quality control and alignment, initial alignment followed by Bayesian propagation of evidence with an expectation-maximization algorithm for read reassignment, and summarization and annotation of results.