Distribution of CRISPR spacer matches in viruses and plasmids of crenarchaeal acidothermophiles and implications for their inhibitory mechanism

• DOI: 10.1042/bst0370023
• Publication Date: 2009-01-22T10:03:13Z
• Authors: Shiraz Ali Shah; Niels R. Hansen; Roger A. Garrett
• Keywords: Extrachromosomal DNA

Transcripts from spacer sequences within chromosomal repeat clusters [CRISPRs (clusters of regularly interspaced palindromic repeats)] archaea have been implicated in inhibiting or regulating the propagation archaeal viruses and plasmids. For crenarchaeal thermoacidophiles, spacers show a high level matches (∼30%) with viral plasmid genomes. Moreover, their distribution along virus/plasmid genomes, as well DNA strand specificity, appear to be random. This is consistent hypothesis that are taken up directly randomly virus transcripts target genomic extrachromosomal elements not transcripts.