ID   REP_BPIF1               Reviewed;         322 AA.
AC   O80302;
DT   15-JUL-1999, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1998, sequence version 1.
DT   03-AUG-2022, entry version 48.
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   Escherichia phage If1 (Bacteriophage If1).
OC   Viruses; Monodnaviria; Loebvirae; Hofneiviricota; Faserviricetes;
OC   Tubulavirales; Inoviridae; Infulavirus.
OX   NCBI_TaxID=10868;
OH   NCBI_TaxID=562; Escherichia coli.
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RA   Hill D.F., Hughes G., McNaughton J.C., Stockwell P.A., Petersen G.B.;
RT   "DNA sequence of the filamentous coliphage If1.";
RL   Submitted (OCT-1993) to the EMBL/GenBank/DDBJ databases.
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=O80302-1; Sequence=Displayed;
CC       Name=G10P; Synonyms=Gene 10 protein;
CC         IsoId=O80302-2; Sequence=VSP_037575;
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; U02303; AAC62160.1; -; Genomic_DNA.
DR   RefSeq; NP_047361.1; NC_001954.1. [O80302-1]
DR   GeneID; 1261860; -.
DR   KEGG; vg:1261860; -.
DR   Proteomes; UP000001833; 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; IPR022688; G2P_C.
DR   Pfam; PF05155; Phage_X; 1.
PE   3: Inferred from homology;
KW   Alternative initiation; DNA replication; DNA-binding; Endonuclease;
KW   Hydrolase; Ligase; Nuclease; Reference proteome.
FT   CHAIN           1..322
FT                   /note="Replication-associated protein G2P"
FT                   /id="PRO_0000098232"
FT   VAR_SEQ         1..223
FT                   /note="Missing (in isoform G10P)"
FT                   /evidence="ECO:0000305"
FT                   /id="VSP_037575"
SQ   SEQUENCE   322 AA;  36501 MW;  364293440EA4C7D3 CRC64;
     MVVSISIRGS LLKVSGNPSR WGRLDNLFGL PTLDSCVSVF NTILAEIGLP QFTKCKRLMP
     GQAKENEKAP LVADGAIIKE VHITSNRAAG KGNEDDYISG LSTQPYRNSV PRLHSNGKSV
     DWLSKKGNVN LIYPTVYNKA HEMELHSLTK IKNRFSEQSR EYNYLLDIIS FCKENGVVRF
     EQKLKSRFLQ KNALNYWGLS DYSILNKLHS DFLELDKKLS VNAMDFETIS DHLVSSGVVE
     TTRAANTTAM YAIQWFHGHV FDFNKKQVQT HRARLRKIGI DIAQKCNVSK FSPVIVKQTR
     EIKVQECVAP SWYVRPSHLR VA