PIRATE

PIRATE clusters and analyses diverged orthologues within bacterial pangenomes to catalogue gene distribution and characterize evolutionary and genetic adaptation patterns.

Key Features:

• Iterative refinement and threshold evaluation: Performs clustering across a broad spectrum of sequence similarity thresholds using iterative refinement.
• Multi-level identity handling: Accommodates both amino acid and nucleotide identity levels for clustering and comparison.
• Orthologous gene family classification: Identifies and classifies orthologous gene families within pangenomes.
• Paralog detection and fission/fusion inference: Detects paralogous gene families and hypothesizes fission/fusion events from clustering patterns.
• Graph-based pangenome organization: Organizes the pangenome using a directed graph structure to represent gene relationships and context.
• Allelic variation and divergence estimation: Estimates sequence divergence for each gene family and provides information on allelic variation.
• Scalability for large datasets: Scales to large-scale whole genome sequencing datasets and to thousands of bacterial isolates with approximately linear performance growth.

Scientific Applications:

• Gene distribution cataloguing: Catalogues presence, absence, and distribution of genes across natural bacterial populations.
• Evolutionary dynamics analysis: Supports investigation of evolutionary dynamics and genetic adaptation mechanisms in bacteria.
• Population diversity assessment: Enables exploration of genetic diversity from clonal to panmictic bacterial species.
• Orthology and paralogy studies: Facilitates analysis of orthology and paralogy relationships within bacterial pangenomes.

Methodology:

Performs iterative clustering across multiple sequence similarity thresholds at amino acid and nucleotide identity levels, detects paralogs and infers fission/fusion events from clustering patterns, constructs a directed graph to organize the pangenome, and estimates sequence divergence per gene family.