Different modes of spacer acquisition by the Staphylococcus epidermidis type III-A CRISPR-Cas system.

ABSTRACT: CRISPR-Cas systems provide prokaryotic organisms with an adaptive defense mechanism that acquires immunological memories of infections. This is accomplished by integration of short fragments from the genome of invaders such as phages and plasmids, called 'spacers', into the CRISPR locus of the host. Depending on their genetic composition, CRISPR-Cas systems can be classified into six types, I-VI, however spacer acquisition has been extensively studied only in type I and II systems. Here, we used an inducible spacer acquisition assay to study this process in the type III-A CRISPR-Cas system of Staphylococcus epidermidis, in the absence of phage selection. Similarly to type I and II spacer acquisition, this type III system uses Cas1 and Cas2 to preferentially integrate spacers from the chrom

SUBMITTER: Aviram N 

PROVIDER: S-EPMC8860600 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature