ID   CAS2_METJA              Reviewed;         114 AA.
AC   Q57831;
DT   01-NOV-1997, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1996, sequence version 1.
DT   03-AUG-2022, entry version 100.
DE   RecName: Full=CRISPR-associated endoribonuclease Cas2;
DE            EC=3.1.-.-;
GN   Name=cas2; OrderedLocusNames=MJ0386;
OS   Methanocaldococcus jannaschii (strain ATCC 43067 / DSM 2661 / JAL-1 / JCM
OS   10045 / NBRC 100440) (Methanococcus jannaschii).
OC   Archaea; Euryarchaeota; Methanomada group; Methanococci; Methanococcales;
OC   Methanocaldococcaceae; Methanocaldococcus.
OX   NCBI_TaxID=243232;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=ATCC 43067 / DSM 2661 / JAL-1 / JCM 10045 / NBRC 100440;
RX   PubMed=8688087; DOI=10.1126/science.273.5278.1058;
RA   Bult C.J., White O., Olsen G.J., Zhou L., Fleischmann R.D., Sutton G.G.,
RA   Blake J.A., FitzGerald L.M., Clayton R.A., Gocayne J.D., Kerlavage A.R.,
RA   Dougherty B.A., Tomb J.-F., Adams M.D., Reich C.I., Overbeek R.,
RA   Kirkness E.F., Weinstock K.G., Merrick J.M., Glodek A., Scott J.L.,
RA   Geoghagen N.S.M., Weidman J.F., Fuhrmann J.L., Nguyen D., Utterback T.R.,
RA   Kelley J.M., Peterson J.D., Sadow P.W., Hanna M.C., Cotton M.D.,
RA   Roberts K.M., Hurst M.A., Kaine B.P., Borodovsky M., Klenk H.-P.,
RA   Fraser C.M., Smith H.O., Woese C.R., Venter J.C.;
RT   "Complete genome sequence of the methanogenic archaeon, Methanococcus
RT   jannaschii.";
RL   Science 273:1058-1073(1996).
CC   -!- FUNCTION: CRISPR (clustered regularly interspaced short palindromic
CC       repeat), is an adaptive immune system that provides protection against
CC       mobile genetic elements (viruses, transposable elements and conjugative
CC       plasmids). CRISPR clusters contain sequences complementary to
CC       antecedent mobile elements and target invading nucleic acids. CRISPR
CC       clusters are transcribed and processed into CRISPR RNA (crRNA).
CC       Functions as a ssRNA-specific endoribonuclease. Involved in the
CC       integration of spacer DNA into the CRISPR cassette (By similarity).
CC       {ECO:0000250}.
CC   -!- COFACTOR:
CC       Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000250};
CC   -!- SUBUNIT: Homodimer, forms a heterotetramer with a Cas1 homodimer.
CC       {ECO:0000250}.
CC   -!- SIMILARITY: Belongs to the CRISPR-associated endoribonuclease Cas2
CC       protein family. {ECO:0000305}.
CC   ---------------------------------------------------------------------------
CC   Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC   Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC   ---------------------------------------------------------------------------
DR   EMBL; L77117; AAB98372.1; -; Genomic_DNA.
DR   PIR; B64348; B64348.
DR   AlphaFoldDB; Q57831; -.
DR   SMR; Q57831; -.
DR   STRING; 243232.MJ_0386; -.
DR   EnsemblBacteria; AAB98372; AAB98372; MJ_0386.
DR   KEGG; mja:MJ_0386; -.
DR   eggNOG; arCOG04194; Archaea.
DR   HOGENOM; CLU_161124_0_1_2; -.
DR   InParanoid; Q57831; -.
DR   OMA; LTHVQNS; -.
DR   PhylomeDB; Q57831; -.
DR   Proteomes; UP000000805; Chromosome.
DR   GO; GO:0004521; F:endoribonuclease activity; IEA:InterPro.
DR   GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-UniRule.
DR   GO; GO:0051607; P:defense response to virus; IEA:UniProtKB-UniRule.
DR   GO; GO:0043571; P:maintenance of CRISPR repeat elements; IEA:UniProtKB-UniRule.
DR   CDD; cd09725; Cas2_I_II_III; 1.
DR   HAMAP; MF_01471; Cas2; 1.
DR   InterPro; IPR021127; CRISPR_associated_Cas2.
DR   InterPro; IPR019199; Virulence_VapD/CRISPR_Cas2.
DR   PANTHER; PTHR34405; PTHR34405; 1.
DR   Pfam; PF09827; CRISPR_Cas2; 1.
DR   TIGRFAMs; TIGR01573; cas2; 1.
PE   3: Inferred from homology;
KW   Antiviral defense; Endonuclease; Hydrolase; Magnesium; Metal-binding;
KW   Nuclease; Reference proteome.
FT   CHAIN           1..114
FT                   /note="CRISPR-associated endoribonuclease Cas2"
FT                   /id="PRO_0000106849"
FT   BINDING         35
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /ligand_note="catalytic"
FT                   /evidence="ECO:0000255"
SQ   SEQUENCE   114 AA;  13655 MW;  2F817459771C9306 CRC64;
     MLKKEWDYVN KILKKIKNIR NLLQDESMYV IIVYDVNVSR VNKIKSFLRK HLNWVQNSVF
     EGEVTKAEFE RIKDGILRII DEDEDSVIIY QFPLNFMPKR EILGLEKNPI DDII