Summary: CRISPR-associated protein Csx8 (Cas_Csx8)
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CRISPR-associated protein Csx8 (Cas_Csx8) Provide feedback
Clusters of short DNA repeats with nonhomologous spacers, which are found at regular intervals in the genomes of phylogenetically distinct prokaryotic species, comprise a family with recognisable features. This family is known as CRISPR (short for Clustered, Regularly Interspaced Short Palindromic Repeats). A number of protein families appear only in association with these repeats and are designated Cas (CRISPR-Associated) proteins. This entry describes proteins of unknown function which are encoded in the midst of a cas gene operon.
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This tab holds annotation information from the InterPro database.
InterPro entry IPR013487
Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) are a family of DNA direct repeats separated by regularly sized non-repetitive spacer sequences that are found in most bacterial and archaeal genomes [PUBMED:17442114]. CRISPRs appear to provide acquired resistance against bacteriophages, possibly acting with an RNA interference-like mechanism to inhibit gene functions of invasive DNA elements [PUBMED:17379808, PUBMED:16545108]. Differences in the number and type of spacers between CRISPR repeats correlate with phage sensitivity. It is thought that following phage infection, bacteria integrate new spacers derived from phage genomic sequences, and that the removal or addition of particular spacers modifies the phage-resistance phenotype of the cell. Therefore, the specificity of CRISPRs may be determined by spacer-phage sequence similarity.
In addition, there are many protein families known as CRISPR-associated sequences (Cas), which are encoded in the vicinity of CRISPR loci [PUBMED:16292354]. CRISPR/cas gene regions can be quite large, with up to 20 different, tandem-arranged cas genes next to a CRISPR cluster or filling the region between two repeat clusters. Cas genes and CRISPRs are found on mobile genetic elements such as plasmids, and have undergone extensive horizontal transfer. Cas proteins are thought to be involved in the propagation and functioning of CRISPRs. Some Cas proteins show similarity to helicases and repair proteins, although the functions of most are unknown. Cas families can be divided into subtypes according to operon organisation and phylogeny.
This entry represents the Cxs8 family of Cas proteins, whose funciton is unknown. These proteins are encoded in the midst of a cas gene operon [PUBMED:16292354].
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Curation and family details
|Author:||TIGRFAMs, Coggill P|
|Number in seed:||3|
|Number in full:||31|
|Average length of the domain:||380.60 aa|
|Average identity of full alignment:||38 %|
|Average coverage of the sequence by the domain:||92.76 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||5|
|Download:||download the raw HMM for this family|
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