ExPASy Proteomics Server

Accession	MF_01125
Dates	31-JAN-2004 (Created) 21-DEC-2009 (Last updated, Version 13)

Data class

Protein

Predictors

HAMAP; MF_01125; [distribution of match scores in UniProtKB];[seed alignment for MF_01125]

Names

Reverse_gyrase

Identifier

RGYR

Protein name

RecName: Full=Reverse gyrase; RecName: Full=Helicase; EC=3.6.1.-; RecName: Full=Topoisomerase; EC=5.99.1.3;

Gene name

rgy

FUNCTION: Modifies the topological state of DNA by introducing positive supercoils in an ATP-dependent process. It cleaves transiently a single DNA strand and remains covalently bound to the 5' DNA end through a tyrosine residue. May be involved in rewinding the DNA strands in the regions of the chromosome that have opened up to allow transcription or replication (By similarity).

CATALYTIC ACTIVITY: ATP-dependent breakage, passage and rejoining of double-stranded DNA.

SUBUNIT: Monomer (By similarity).

DOMAIN: Both the DNA unwinding and positive supercoiling activities require the cooperation of both domains. The cooperative action between the helicase-like and the topoisomerase domains is specific. The helicase-like domain probably does not directly unwind DNA but acts more likely by driving ATP-dependent conformational changes within the whole enzyme, functioning more like a protein motor. The "latch" region of the N-terminal domain plays a regulatory role in the enzyme, repressing topoisomerase activity in the absence of ATP and therefore preventing the enzyme from acting as an ATP-independent relaxing enzyme; it also helps to coordinate nucleotide hydrolysis by the ATPase domain with the supercoiling activity of the topoisomerase domain (By similarity).

MISCELLANEOUS: This enzyme is the only unique feature of hyperthermophilic bacteria/archaea discovered so far. It appears to be essential for adaptation to life at high temperatures.

SIMILARITY: In the N-terminal section; belongs to the DEAD box helicase family. DDVD subfamily.

SIMILARITY: In the C-terminal section; belongs to the prokaryotic type I/III topoisomerase family.

SIMILARITY: Contains 1 helicase domain.

Pfam	PF00270; DEAD; 1; PF01131; Topoisom_bac; 1; PF01751; Toprim; 1; trigger=Yes; PF00271; Helicase_C; 1;
PRINTS	PR00417; PRTPISMRASEI; 1;
TIGRFAMs	TIGR01054; rgy; 1;

Hydrolase, Isomerase, Topoisomerase, Helicase, DNA-binding, ATP-binding, Nucleotide-binding.

Metal-binding, Zinc, Zinc-finger.

GO:0005524; Molecular function: ATP binding.
GO:0003677; Molecular function: DNA binding.
GO:0003918; Molecular function: DNA topoisomerase (ATP-hydrolyzing) activity.
GO:0004386; Molecular function: helicase activity.

GO:0008270; Molecular function: zinc ion binding.

GO:0006265; Biological process: DNA topological change.
GO:0006268; Biological process: DNA unwinding during replication.

From: RGYR_PYRFU (P95479)
Key		From		To		Description		Condition		FTGroup
DOMAIN		Nter		644		Helicase
ZN_FING		9		30		C4-type 1 (By similarity)		C-x-x-C-x(10,18)-[CH]-x-x-C
NP_BIND		106		113		ATP (By similarity)		x-P-x-G-x-G-K-[ST]
ZN_FING		722		741		C4-type 2 (By similarity)		C-x-x-C-x(10,18)-C-x-x-C
REGION		645		Cter		Topoisomerase I
MOTIF		213		216		DDVD box		D-D-V-D
ACT_SITE		955		955		For DNA cleavage activity (By similarity)		Y
BINDING		89		89		ATP (By similarity)		Q

Size range:	1054-1624 amino acids
Related UniRules:	None
Template:	Q08582 (RGYR_SULAC); O29238 (RGYR_ARCFU): [Recover all]
Scope:	Bacteria; Aquificales Bacteria; Thermoanaerobacteriales Bacteria; Thermotogales Archaea
Fusion:	Nter: None; Cter: None
Duplicate:	in AERPE, AQUAE, SULSO, SULTO
Plasmid encoded:	None
Comments:	The reverse gyrases of M. jannaschii and P. horikoshii contain inteins which were excised in the alignment