The helicase in many CRISPR-associated (cas) gene clusters is designated Cas3, and most Cas3 proteins are described by model TIGR01587. Members of this family are considerably larger, show a number of motifs in common with TIGR01587 sequences, and replace Cas3 in some CRISPR/cas loci in a number of Proteobacteria, including Yersinia pestis, Chromobacterium violaceum, Erwinia carotovora subsp. atroseptica SCRI1043, Photorhabdus luminescens subsp. laumondii TTO1, Legionella pneumophila, etc.
Jiyao W et al.(2023). "The conserved domain database in 2023.",