ID   CAS1_CLOSS              Reviewed;         301 AA.
AC   F7V5D5;
DT   16-MAY-2012, integrated into UniProtKB/Swiss-Prot.
DT   16-MAY-2012, sequence version 2.
DT   03-AUG-2022, entry version 44.
DE   RecName: Full=CRISPR-associated endonuclease Cas1 {ECO:0000255|HAMAP-Rule:MF_01470};
DE            EC=3.1.-.- {ECO:0000255|HAMAP-Rule:MF_01470};
GN   Name=cas1 {ECO:0000255|HAMAP-Rule:MF_01470}; OrderedLocusNames=CXIVA_19970;
OS   Clostridium sp. (strain SY8519).
OC   Bacteria; Firmicutes; Clostridia; Eubacteriales; Clostridiaceae;
OC   Clostridium.
OX   NCBI_TaxID=1042156;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=SY8519;
RX   PubMed=21914882; DOI=10.1128/jb.05637-11;
RA   Yokoyama S., Oshima K., Nomura I., Hattori M., Suzuki T.;
RT   "Complete genomic sequence of the O-desmethylangolensin-producing bacterium
RT   Clostridium rRNA cluster XIVa strain SY8519, isolated from adult human
RT   intestine.";
RL   J. Bacteriol. 193:5568-5569(2011).
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 spacers, sequences complementary to
CC       antecedent mobile elements, and target invading nucleic acids. CRISPR
CC       clusters are transcribed and processed into CRISPR RNA (crRNA). Acts as
CC       a dsDNA endonuclease. Involved in the integration of spacer DNA into
CC       the CRISPR cassette. {ECO:0000255|HAMAP-Rule:MF_01470}.
CC   -!- COFACTOR:
CC       Name=Mg(2+); Xref=ChEBI:CHEBI:18420;
CC         Evidence={ECO:0000255|HAMAP-Rule:MF_01470};
CC       Name=Mn(2+); Xref=ChEBI:CHEBI:29035;
CC         Evidence={ECO:0000255|HAMAP-Rule:MF_01470};
CC   -!- SUBUNIT: Homodimer, forms a heterotetramer with a Cas2 homodimer.
CC       {ECO:0000255|HAMAP-Rule:MF_01470}.
CC   -!- SIMILARITY: Belongs to the CRISPR-associated endonuclease Cas1 family.
CC       {ECO:0000255|HAMAP-Rule:MF_01470}.
CC   -!- SEQUENCE CAUTION:
CC       Sequence=BAK47964.1; Type=Erroneous initiation; Note=Truncated N-terminus.; Evidence={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; AP012212; BAK47964.1; ALT_INIT; Genomic_DNA.
DR   RefSeq; WP_050979269.1; NC_015737.1.
DR   AlphaFoldDB; F7V5D5; -.
DR   SMR; F7V5D5; -.
DR   STRING; 1042156.CXIVA_19970; -.
DR   EnsemblBacteria; BAK47964; BAK47964; CXIVA_19970.
DR   KEGG; cls:CXIVA_19970; -.
DR   eggNOG; COG1518; Bacteria.
DR   HOGENOM; CLU_1624342_0_0_9; -.
DR   OrthoDB; 1581397at2; -.
DR   Proteomes; UP000008937; Chromosome.
DR   GO; GO:0003677; F:DNA binding; IEA:UniProtKB-KW.
DR   GO; GO:0004520; F:endodeoxyribonuclease 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; cd09719; Cas1_I-E; 1.
DR   Gene3D; 1.20.120.920; -; 1.
DR   Gene3D; 3.100.10.20; -; 1.
DR   HAMAP; MF_01470; Cas1; 1.
DR   InterPro; IPR033641; Cas1_I-E.
DR   InterPro; IPR002729; CRISPR-assoc_Cas1.
DR   InterPro; IPR042206; CRISPR-assoc_Cas1_C.
DR   InterPro; IPR019851; CRISPR-assoc_Cas1_ECOLI.
DR   InterPro; IPR042211; CRISPR-assoc_Cas1_N.
DR   Pfam; PF01867; Cas_Cas1; 1.
DR   TIGRFAMs; TIGR00287; cas1; 1.
DR   TIGRFAMs; TIGR03638; cas1_ECOLI; 1.
PE   3: Inferred from homology;
KW   Antiviral defense; DNA-binding; Endonuclease; Hydrolase; Magnesium;
KW   Manganese; Metal-binding; Nuclease; Reference proteome.
FT   CHAIN           1..301
FT                   /note="CRISPR-associated endonuclease Cas1"
FT                   /id="PRO_0000417076"
FT   BINDING         133
FT                   /ligand="Mn(2+)"
FT                   /ligand_id="ChEBI:CHEBI:29035"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_01470"
FT   BINDING         200
FT                   /ligand="Mn(2+)"
FT                   /ligand_id="ChEBI:CHEBI:29035"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_01470"
FT   BINDING         213
FT                   /ligand="Mn(2+)"
FT                   /ligand_id="ChEBI:CHEBI:29035"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_01470"
SQ   SEQUENCE   301 AA;  33562 MW;  005209CB9F4FC000 CRC64;
     MPRISDRVTY IYVEHSKINR VDGSITVAES RGIVRIPASM IGILLLGPGT DISHRAMELL
     GDSGTSVAWV GEQGVRNYAH GRSLSHTSRF LELQAKLVSN TRSRLQVARK MYQMRFPEED
     VSSLTMQQLR AKEGARIRKI YRKMSAEYGV DWNGRTYDPD DFEGGDPVNQ ALSAANVALY
     GLAYSAIAAM GLATGLGFVH TGHDLSFVYD IADLYKADIT VPVAFEIASE YEEGDNVGKI
     SRQKVRDKFI GGKLFATIVR DIQLLFGIKE EEQLNVEPLS LWDNREGNIK YGINYSNENE
     D