HAMAP

Accession	MF_01129
Dates	22-JUL-2003 (Created) 15-OCT-2010 (Last updated, Version 30)

Data class

Protein

Predictors

HAMAP; MF_01129; [distribution of match scores in UniProtKB];[seed alignment for MF_01129]

Names

PPase-energized_pump

Identifier

HPPA

Protein name

RecName: Full=Putative K(+)-stimulated pyrophosphate-energized sodium pump; EC=3.6.1.1; AltName: Full=Membrane-bound sodium-translocating pyrophosphatase; AltName: Full=Pyrophosphate-energized inorganic pyrophosphatase; Short=Na(+)-PPase;

Protein name

RecName: Full=K(+)-insensitive pyrophosphate-energized proton pump; EC=3.6.1.1; AltName: Full=Membrane-bound proton-translocating pyrophosphatase; AltName: Full=Pyrophosphate-energized inorganic pyrophosphatase; Short=H(+)-PPase;

Protein name

RecName: Full=Pyrophosphate-energized proton pump; EC=3.6.1.1; AltName: Full=Membrane-bound proton-translocating pyrophosphatase; AltName: Full=Pyrophosphate-energized inorganic pyrophosphatase; Short=H(+)-PPase;

Gene name

hppA

FUNCTION: Sodium pump that utilizes the energy of pyrophosphate hydrolysis as the driving force for Na(+) movement across the membrane (By similarity).

FUNCTION: Proton pump that utilizes the energy of pyrophosphate hydrolysis as the driving force for proton movement across the membrane. Generates a proton motive force (By similarity).

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

COFACTOR: Magnesium (By similarity).

ENZYME REGULATION: Requires K(+) for maximal activity (By similarity).

SUBUNIT: Homodimer (By similarity).

SUBCELLULAR LOCATION: Cell membrane; Multi-pass membrane protein (By similarity).

SIMILARITY: Belongs to the H(+)-translocating pyrophosphatase (TC 3.A.10) family. K(+)-stimulated subfamily.

SIMILARITY: Belongs to the H(+)-translocating pyrophosphatase (TC 3.A.10) family. K(+)-insensitive subfamily.

SIMILARITY: Belongs to the H(+)-translocating pyrophosphatase (TC 3.A.10) family.

Pfam	PF03030; H_PPase; 1;
TIGRFAMs	TIGR01104; V_PPase; 1;
PIRSF	PIRSF001265; H+-PPase; 1;
General	Transmembrane; -; 13-18; trigger=Yes;

Cell membrane, Hydrolase, Ion transport, Magnesium, Membrane.

Potassium, Sodium, Sodium transport.

Hydrogen ion transport.

Transmembrane, Transmembrane helix, Transport.

GO:0009678; Molecular function: hydrogen-translocating pyrophosphatase activity.
GO:0004427; Molecular function: inorganic diphosphatase activity.
GO:0000287; Molecular function: magnesium ion binding.

GO:0030955; Molecular function: potassium ion binding.
GO:0006814; Biological process: sodium ion transport.

GO:0015992; Biological process: proton transport.

GO:0005887; Cellular component: integral to plasma membrane.

From: HPPA_THEMA (Q9S5X0)
Key		From		To		Description		Condition		FTGroup
SITE (Optional)		495		495		Determinant of potassium dependence (By similarity)		A
From: HPPA_PYRAE (Q8ZWI8)
SITE (Optional)		476		476		Determinant of potassium independence (By similarity)		K

Size range:	655-825 amino acids
Related UniRules:	None
Template:	Q9S5X0 (HPPA_THEMA); Q3AFC6 (HPPA_CARHZ); Q8ZWI8 (HPPA_PYRAE); Q8PYZ8 (HPPA1_METMA): [Recover all]
Scope:	Bacteria Archaea
Fusion:	Nter: None; Cter: None
Duplicate:	in METAC, METMA, MOOTA
Plasmid encoded:	None
Comments:	There are two classes of pyrophosphate-energized pumps, differing in K(+) sensitivity (PubMed:17454298). Three members of the K(+)-stimulated subfamily have been characterized as sodium pumps (PubMed:17605473). Further characterization is needed to distinguish Na(+) transporters from H(+) transporters.