AC   MF_01453;
DC   Protein; auto
TR   HAMAP; MF_01453; -; 1; level=0
XX
Names: AddB_type2
XX
ID   ADDB
DE   RecName: Full=ATP-dependent helicase/deoxyribonuclease subunit B;
DE            EC=3.1.-.-;
DE   AltName: Full=ATP-dependent helicase/nuclease subunit RexB;
GN   Name=rexB;
XX
CC   -!- FUNCTION: The heterodimer acts as both an ATP-dependent DNA helicase
CC       and an ATP-dependent, dual-direction single-stranded exonuclease.
CC       Recognizes the chi site generating a DNA molecule suitable for the
CC       initiation of homologous recombination. This subunit has 5' -> 3'
CC       nuclease activity but not helicase activity.
case <FTGroup:1>
CC   -!- COFACTOR:
CC       Name=[4Fe-4S] cluster; Xref=ChEBI:CHEBI:49883;
CC       Note=Binds 1 [4Fe-4S] cluster.;
end case
CC   -!- COFACTOR:
CC       Name=Mg(2+); Xref=ChEBI:CHEBI:18420;
CC   -!- SUBUNIT: Heterodimer of AddA and RexB.
CC   -!- MISCELLANEOUS: Despite having helicase-like domains, this subunit does
CC       not have helicase activity.
CC   -!- SIMILARITY: Belongs to the helicase family. AddB/RexB type 2 subfamily.
XX
DR   Pfam; PF21445; ADDB_N; 1; trigger=no
DR   Pfam; PF12705; PDDEXK_1; 1; trigger=no
DR   NCBIfam; TIGR02774; RexB_recomb; 0-1; trigger=no
XX
KW   ATP-binding
KW   DNA damage
KW   DNA repair
KW   DNA-binding
KW   Exonuclease
KW   Helicase
KW   Hydrolase
KW   Nuclease
KW   Nucleotide-binding
case <FTGroup:1>
KW   4Fe-4S
KW   Iron
KW   Iron-sulfur
KW   Metal-binding
end case
XX
GO   GO:0005524; F:ATP binding
GO   GO:0008409; F:5'-3' exonuclease activity
GO   GO:0003690; F:double-stranded DNA binding
case <FTGroup:1>
GO   GO:0051536; F:iron-sulfur cluster binding
end case
GO   GO:0000724; P:double-strand break repair via homologous recombination
XX
FT   From: ADDB_LACLM (A2RH76)
FT   BINDING         766
FT                   /ligand="[4Fe-4S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:49883"
FT   Optional; Group: 1; Condition: C
FT   BINDING         1056
FT                   /ligand="[4Fe-4S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:49883"
FT   Optional; Group: 1; Condition: C
FT   BINDING         1059
FT                   /ligand="[4Fe-4S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:49883"
FT   Optional; Group: 1; Condition: C
FT   BINDING         1065
FT                   /ligand="[4Fe-4S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:49883"
FT   Optional; Group: 1; Condition: C
XX
Size: 1071-1260;
Related: MF_01452;
Template: A2RH76; Q97QQ0;
Scope:
 Bacteria; Bacillota
Fusion:
 Nter: None
 Cter: None
Duplicate: None
Plasmid: None
Comments: The iron-sulfur center has been shown to exist in the related
 AddB protein from B.subtilis; its suggested presence in a few members of
 this family is based solely on sequence conservation.
 Two related subfamiles of this protein exist; addB in Bacillus and
 Staphylococcus (MF_01452), and rexB in Lactobacillus and Streptococcus
 (this family). In most Lactobacillales there is no 4Fe-4S center; this has
 been suggested (PubMed:19129187) to occur in organisms which inhabit a low-
 iron environment.
XX
# Revision 1.20 2023/11/10
//