HAMAP

Accession	MF_01452
Dates	4-JUN-2009 (Created) 18-AUG-2010 (Last updated, Version 7)

Data class

Protein

Predictors

HAMAP; MF_01452; [distribution of match scores in UniProtKB];[seed alignment for MF_01452]

Names

AddB_type1

Identifier

ADDB

Protein name

RecName: Full=ATP-dependent helicase/deoxyribonuclease subunit B; EC=3.1.-.-; EC=3.6.4.12; AltName: Full=ATP-dependent helicase/nuclease AddB;

Gene name

addB

FUNCTION: The heterodimer acts as both an ATP-dependent DNA helicase and an ATP-dependent, dual-direction single-stranded exonuclease. Recognizes the chi site generating a DNA molecule suitable for the initiation of homologous recombination. The AddB nuclease domain is not required for chi fragment generation; this subunit has 5' -> 3' nuclease activity (By similarity).

CATALYTIC ACTIVITY: ATP + H(2)O = ADP + phosphate.

COFACTOR: Binds 1 4Fe-4S cluster. Magnesium (By similarity).

COFACTOR: Magnesium (By similarity).

SUBUNIT: Heterodimer of AddA and AddB (By similarity).

SIMILARITY: Belongs to the helicase family. AddB/RexB type 1 subfamily.

PROSITE	PS51198; UVRD_HELICASE_ATP_BIND; 1; trigger=PRU00560; PS51217; UVRD_HELICASE_CTER; 1; trigger=PRU00617;
Pfam	PF00580; UvrD-helicase; 1; PF04257; Exonuc_V_gamma; 1;
TIGRFAMs	TIGR02773; addB_Gpos; 1;

ATP-binding, DNA damage, DNA repair, Exonuclease, Hydrolase, Nuclease, Nucleotide-binding.

4Fe-4S, Iron, Iron-sulfur, Metal-binding.

GO:0005524; Molecular function: ATP binding.
GO:0008409; Molecular function: 5'-3' exonuclease activity.
GO:0003690; Molecular function: double-stranded DNA binding.

GO:0051536; Molecular function: iron-sulfur cluster binding.

GO:0000724; Biological process: double-strand break repair via homologous recombination.

From: ADDB_BACSU (P23477)
Key		From		To		Description		Condition		FTGroup
METAL (Optional)		801		801		Iron-sulfur (4Fe-4S) (By similarity)		C		1
METAL (Optional)		1121		1121		Iron-sulfur (4Fe-4S) (By similarity)		C		1
METAL (Optional)		1124		1124		Iron-sulfur (4Fe-4S) (By similarity)		C		1
METAL (Optional)		1130		1130		Iron-sulfur (4Fe-4S) (By similarity)		C		1

Size range:	1134-1224 amino acids
Related UniRules:	MF_01453 (ADDB)
Template:	P23477 (ADDB_BACSU)
Scope:	Bacteria; Firmicutes
Fusion:	Nter: None; Cter: None
Duplicate:	None
Plasmid encoded:	None
Comments:	Two related subfamiles of this protein exist; addB in Bacillus and Staphylococcus (this family), and rexB in Lactobacillus and Streptococcus (MF_01453). 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. Not all members match the uvrD_helicase profiles (PS51198 and PS51217).