PHIST

PHIST predicts prokaryotic hosts for phages from metagenomic sequences by identifying shared k-mers (exact matches) between viral and host genomes.

Key Features:

• Host Prediction Accuracy: Improves species-level host prediction accuracy, exceeding alignment-based tools by approximately 3 percentage points and outperforming alignment-free and CRISPR-based approaches by 14–20 percentage points.
• Speed and Efficiency: Achieves computational speed approximately two orders of magnitude faster than traditional alignment-based tools, enabling large-scale metagenomic processing.
• Technical Implementation: Implemented in C++ with a Python API and released under the GNU license.

Scientific Applications:

• Microbial Ecology: Enables inference of virus–host associations to study microbial ecosystem structure and interactions.
• Virus Evolution: Supports investigations of virus evolution through host association data.
• Phage Therapy Dynamics: Informs studies on phage therapy by revealing host ranges and host–virus dynamics.
• Environmental Metagenomics: Facilitates rapid identification of viral-host interactions in environmental metagenomic datasets to inform biodiversity and ecological function studies.

Methodology:

Identifies exact k-mer matches and analyzes k-mer overlaps between viral and prokaryotic host genomic sequences, using exact-match k-mer overlap analysis rather than sequence alignment or CRISPR spacer matching for host prediction.