UNITE database

UNITE database curates a reference database of fungal internal transcribed spacer (ITS) sequences to support molecular identification and taxonomic assignment of fungi.

Key Features:

• Reference dataset development: Curates an inclusive public reference dataset of fungal ITS sequences drawn from international nucleotide sequence databases, including species represented by at least two ITS sequences.
• Unique species identifiers: Assigns unique, stable identifiers to taxa based on accession numbers (e.g., Hymenoscyphus pseudoalbidus|GU586904|SH133781.05FU).
• Species Hypotheses (SH): Generates species hypotheses by clustering ITS sequences at similarity thresholds (97–99%), with each SH represented by a designated reference sequence selectable automatically or manually.
• Continuous updates and community annotations: Maintains dynamic updates as the public fungal ITS sequence corpus grows and incorporates third-party taxonomic and ecological annotations.
• Integration with bioinformatics pipelines: Provides reference sequences for local sequence similarity searches and integration into pipelines such as QIIME.

Scientific Applications:

• Taxonomic assignment of ITS sequences: Enables molecular identification and taxonomic assignment of environmental fungal ITS sequences.
• Fungal biodiversity and species delimitation: Supports species delineation and biodiversity studies through SH-based clustering of ITS sequences.
• Metagenomic analyses and environmental monitoring: Facilitates metagenomic workflows and environmental monitoring by supplying curated ITS reference sequences compatible with tools like QIIME.
• Ecological assessment and conservation: Provides standardized reference data to inform ecological assessments and conservation studies involving fungal taxa.

Methodology:

Clusters ITS sequences into species hypotheses using similarity thresholds (97–99%) and a distance metric implemented in 0.5% steps between species, represents each SH by a designated reference sequence (automatic or manual selection), and incorporates distributed third-party taxonomic and ecological annotations.