ID   REP_BPI22               Reviewed;         344 AA.
AC   P15419;
DT   01-APR-1990, integrated into UniProtKB/Swiss-Prot.
DT   01-APR-1990, sequence version 1.
DT   03-AUG-2022, entry version 80.
DE   RecName: Full=Replication-associated protein G2P;
DE            Short=Rep;
DE            EC=3.1.21.-;
DE            EC=6.5.1.1;
DE   AltName: Full=G2P;
DE   AltName: Full=Gene 2 protein;
GN   Name=II;
OS   Enterobacteria phage I2-2 (Bacteriophage I2-2).
OC   Viruses; Monodnaviria; Loebvirae; Hofneiviricota; Faserviricetes;
OC   Tubulavirales; Inoviridae; Lineavirus.
OX   NCBI_TaxID=10869;
OH   NCBI_TaxID=562; Escherichia coli.
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RX   PubMed=1556749; DOI=10.1007/bf00182391;
RA   Stassen A.P., Schonmakers E.F., Yu M., Schoenmakers J.G., Konings R.N.H.;
RT   "Nucleotide sequence of the genome of the filamentous bacteriophage I2-2:
RT   module evolution of the filamentous phage genome.";
RL   J. Mol. Evol. 34:141-152(1992).
CC   -!- FUNCTION: Isoform G2P plays an essential role in viral DNA replication.
CC       Binds the origin of replication and cleaves the dsDNA replicative form
CC       I (RFI) and becomes covalently bound to it via phosphotyrosine bond,
CC       generating the dsDNA replicative form II (RFII). In turn, viral DNA
CC       replication initiates at the 3'-OH of the cleavage site. After one
CC       round of rolling circle synthesis, protein G2P is linked to the newly
CC       synthesized ssDNA and joins the ends of the displaced strand to
CC       generate a circular single-stranded molecule ready to be packed into a
CC       virion. {ECO:0000250}.
CC   -!- FUNCTION: Isoform G10P protein binds to double-stranded DNA and
CC       prevents hydrolysis by nucleases. Additionally, G10P is an inhibitor of
CC       DNA replication and may have a role in the transition from
CC       semiconservative replicative form DNA replication to single-stranded
CC       DNA synthesis in the life cycle. {ECO:0000250}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=ATP + (deoxyribonucleotide)n-3'-hydroxyl + 5'-phospho-
CC         (deoxyribonucleotide)m = (deoxyribonucleotide)n+m + AMP +
CC         diphosphate.; EC=6.5.1.1;
CC   -!- ALTERNATIVE PRODUCTS:
CC       Event=Alternative initiation; Named isoforms=2;
CC       Name=G2P; Synonyms=Gene 2 protein;
CC         IsoId=P15419-1; Sequence=Displayed;
CC       Name=G10P; Synonyms=Gene 10 protein;
CC         IsoId=P15419-2; Sequence=VSP_018672;
CC   -!- SIMILARITY: Belongs to the inovirus G2P 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; X14336; CAA32521.1; -; Genomic_DNA.
DR   EMBL; X14336; CAA32522.1; -; Genomic_DNA.
DR   PIR; S08085; S08085.
DR   RefSeq; NP_039615.1; NC_001332.1. [P15419-1]
DR   RefSeq; NP_039616.1; NC_001332.1. [P15419-2]
DR   GeneID; 1260717; -.
DR   GeneID; 1260718; -.
DR   KEGG; vg:1260717; -.
DR   KEGG; vg:1260718; -.
DR   Proteomes; UP000000373; Genome.
DR   GO; GO:0003677; F:DNA binding; IEA:UniProtKB-KW.
DR   GO; GO:0003910; F:DNA ligase (ATP) activity; IEA:UniProtKB-EC.
DR   GO; GO:0004519; F:endonuclease activity; IEA:UniProtKB-KW.
DR   GO; GO:0006260; P:DNA replication; IEA:UniProtKB-KW.
DR   InterPro; IPR006516; G2P.
DR   InterPro; IPR022688; G2P_C.
DR   InterPro; IPR022686; G2P_N.
DR   Pfam; PF05144; Phage_CRI; 1.
DR   Pfam; PF05155; Phage_X; 1.
DR   TIGRFAMs; TIGR01629; rep_II_X; 1.
PE   3: Inferred from homology;
KW   Alternative initiation; DNA replication; DNA-binding; Endonuclease;
KW   Hydrolase; Ligase; Nuclease; Reference proteome.
FT   CHAIN           1..344
FT                   /note="Replication-associated protein G2P"
FT                   /id="PRO_0000003309"
FT   VAR_SEQ         1..246
FT                   /note="Missing (in isoform G10P)"
FT                   /evidence="ECO:0000305"
FT                   /id="VSP_018672"
SQ   SEQUENCE   344 AA;  38843 MW;  62D84559DA95BA0F CRC64;
     MIDWVTAVLP CLHVPVDAGR VLSVAPDGSV EWESVKFSRV TGSFQSSISV RSQGSDGNGK
     ATHLYVDGNP SKWLQGHNIV GSDDLNGLMI AFYARMLSLL NIPHHLESYR QVLSGQYELK
     RVDINYMFEL PTLIDVRSWL HAAEFKAKTR HGRPATAKGT LYFGKNSRRW SIKAYSKYDE
     VNCGKKAHGV PEEIKKTGLV EWSKNKLRLE LTLRALQLTD INLNFAKNWS TETAYTVFKE
     YMGRIEMSGN TLLTDTQVIN LPSALRMTYV CWKQGICVTD MVSRATYFRH RKVLKEFGID
     IAVTVDRVDN SNVVPLIRVL EAKPASIPSQ YDNLIFSSNR VSSF