CRISPRcompar: a website to compare clustered regularly interspaced short palindromic repeats.

ABSTRACT: Clustered regularly interspaced short palindromic repeat (CRISPR) elements are a particular family of tandem repeats present in prokaryotic genomes, in almost all archaea and in about half of bacteria, and which participate in a mechanism of acquired resistance against phages. They consist in a succession of direct repeats (DR) of 24-47 bp separated by similar sized unique sequences (spacers). In the large majority of cases, the direct repeats are highly conserved, while the number and nature of the spacers are often quite diverse, even among strains of a same species. Furthermore, the acquisition of new units (DR + spacer) was shown to happen almost exclusively on one side of the locus. Therefore, the CRISPR presents an interesting genetic marker for comparative and evolutionary analysis

SUBMITTER: Grissa I 

PROVIDER: S-EPMC2447796 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature