Members of this family as found in CRISPR-associated (cas) gene regions in Streptococcus thermophilus CNRZ1066, Staphylococcus epidermidis RP62A, and Mycobacterium tuberculosis (strains CDC1551 and H37Rv), as part of Mtube-type CRISPR/Cas systems. CRISPR is a widespread form of direct repeat found in archaea and bacteria, with distinctive subtypes each of which has a characteristic sporadic distribution.
Jiyao W et al.(2023). "The conserved domain database in 2023.",