%0 Journal Article %A Han, Xiao %A Zhou, Xingya %A Pei, Zhangming %A Stanton, Catherine %A Ross, R. Paul %A Zhao, Jianxin %A Zhang, Hao %A Yang, Bo %A Chen, Wei %T Characterization of CRISPR-Cas systems in Bifidobacterium breve %D 2022 %J Microbial Genomics, %V 8 %N 4 %@ 2057-5858 %C 000812 %R https://doi.org/10.1099/mgen.0.000812 %K genotyping %K prophage %K CRISPR-Cas system %K Bifidobacterium breve %I Microbiology Society, %X The clustered regularly interspaced short palindromic repeat (CRISPR)-CRISPR-associated protein (Cas) system is an important adaptive immune system for bacteria to resist foreign DNA infection, which has been widely used in genotyping and gene editing. To provide a theoretical basis for the application of the CRISPR-Cas system in Bifidobacterium breve , the occurrence and diversity of CRISPR-Cas systems were analysed in 150 B. breve strains. Specifically, 47 % (71/150) of B. breve genomes possessed the CRISPR-Cas system, and type I-C CRISPR-Cas system was the most widely distributed among those strains. The spacer sequences present in B. breve can be used as a genotyping marker. Additionally, the phage assembly-related proteins were important targets of the type I-C CRISPR-Cas system in B. breve , and the protospacer adjacent motif sequences were further characterized in B. breve type I-C system as 5′-TTC-3′. All these results might provide a molecular basis for the development of endogenous genome editing tools in B. breve . %U https://www.microbiologyresearch.org/content/journal/mgen/10.1099/mgen.0.000812