UNASSIGNED: The CRISPR-Cas (Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR associated genes) system provides prokaryotic cells with an adaptive and heritable immune response to foreign genetic elements such as viruses, plasmids, and transposons. It is present in the majority of Archaea and almost half of Bacteria species. @entity2523 is an important @entity1 pathogen, proven to be an etiological agent in @entity2521 , and has been linked to systemic conditions like @entity309 and @entity65 . At least 95% of clinical strains of @entity2523 encode CRISPR arrays, suggesting that they play an important function in vivo. Here, we show that all four CRISPR arrays present in the @entity40672 genome are transcribed. For one of the arrays, we demonstrate in vivo activity against double-stranded DNA constructs containing protospacer sequences accompanied on their 3' end by NGG protospacer-adjacent motif (PAM). Most of the 44 spacers present in the genome of @entity40672 share no significant similarity with any known sequences, although four spacers are similar to sequences from bacteria found in the oral cavity and gastrointestinal tract. Four spacers match genomic sequences of the host, however none of these is flanked at its 3' terminus by the appropriate PAM element. Importance The CRISPR-Cas (Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR associated genes) is a unique system that provides prokaryotic cells with an adaptive and heritable immunity. In this manuscript we showed here that CRISPR-Cas system of the @entity2523 bacterium, an important @entity1 pathogen associated with @entity2521 and possibly also other conditions like @entity309 and @entity65 , is active and provides protection from foreign genetic elements. Importantly, presented data may be useful for better understanding of the communication between cells in larger bacterial communities and, consequently, the process of the disease development and progression.

Functional analysis of XXXX CRISPR-Cas systems.

@entity1 :: ('9606', 'Species') :: ['human'] @entity309 :: ('MESH:D001172', 'Disease') :: ['rheumatoid arthritis'] @entity2521 :: ('MESH:D010518', 'Disease') :: ['periodontitis'] @entity40672 :: ('242619', 'Species') :: ['P. gingivalis W83'] @entity65 :: ('MESH:D002318', 'Disease') :: ['cardiovascular disease'] @entity2523 :: ('837', 'Species') :: ['Porphyromonas gingivalis', 'P. gingivalis']
@entity40672 :: (242619,Species) :: ['Porphyromonas gingivalis W83']
