CRISPR (clustered regularly interspaced short palindromic repeats) & Microbiomes / Microbiotas

CRISPR are found in approximately 50% of sequenced bacterial genomes and nearly 90% of sequenced archaea. These sequences are derived from DNA fragments of bacteriophages that had previously infected the prokaryote. These Sequences Play a Key Role in the Antiviral (i.e. Anti-phage) Defense System of Prokaryotes

Many bacteria resist invasive DNA by incorporating sequences into CRISPR loci, which enable sequence-specific degradation. While CRISPR systems have been well studied from isolate genomes, culture-independent metagenomics provide a new window into their diversity.

We profiled CRISPR loci and cas genes in the body-wide human microbiome using 2,355 metagenomes. This approach yielded functional and taxonomic profiles for 2.9 million spacers by aligning the spacer content to each sample’s metagenome and …