CRISPRs Database

CRISPRs Database (CRISPRdb) provides a curated repository of CRISPR arrays, repeats, and spacer sequences from archaeal and bacterial genomes to support structural and evolutionary analyses of CRISPR systems.

Key Features:

• Automated Identification and Extraction: Uses the CRISPRFinder program to identify CRISPR arrays and extract repeat and spacer sequences from genomic data.
• Regular Updates: Incorporates newly released genome sequences on a monthly basis.
• Comprehensive Data Collection: Contains nearly six hundred CRISPRs identified across 475 published genomes.
• Alignment Tools: Performs alignment of flanking sequences to identify similarities between different loci.
• Unique Sequence Dictionaries: Includes utilities to build dictionaries of unique spacer sequences for polymorphism and evolutionary analyses.

Scientific Applications:

• CRISPR Structure and Evolution: Enables analysis of the addition of new motifs (spacers and repeats) at one end of CRISPR arrays to study diversification mechanisms.
• Intra-species Polymorphism: Supports studies of CRISPR variation within species to investigate adaptive roles against viral elements.
• Comparative Genomics: Facilitates comparison of CRISPR arrays across organisms to assess distribution and functional implications.

Methodology:

CRISPRdb applies CRISPRFinder to scan genomic sequences for characteristic repeat–spacer patterns, aligns flanking sequences to detect locus similarities, and constructs dictionaries of unique spacer sequences.