Q4J9L0 · FLAI_SULAC
- ProteinArchaeal flagellar ATPase motor FlaI
- GeneflaI
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids513 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Component of the archaellum (PubMed:22081969, PubMed:23416110, PubMed:24103130, PubMed:26508112).
FlaX, FlaH and FlaI form the core cytoplasmic motor complex of the crenarchaeal archaellum (PubMed:24103130, PubMed:26508112).
FlaI shows ATPase activity, which provides the energy for both archaellum assembly and rotation (PubMed:21506936, PubMed:23416110).
Hydrolyzes ATP with the highest rate, but is also able to hydrolyze GTP, CTP and UTP (PubMed:21506936).
Cannot hydrolyze ADP into AMP (PubMed:21506936).
FlaX, FlaH and FlaI form the core cytoplasmic motor complex of the crenarchaeal archaellum (PubMed:24103130, PubMed:26508112).
FlaI shows ATPase activity, which provides the energy for both archaellum assembly and rotation (PubMed:21506936, PubMed:23416110).
Hydrolyzes ATP with the highest rate, but is also able to hydrolyze GTP, CTP and UTP (PubMed:21506936).
Cannot hydrolyze ADP into AMP (PubMed:21506936).
Catalytic activity
- ATP + H2O = ADP + H+ + phosphateThis reaction proceeds in the forward direction.
Cofactor
Ca2+ (UniProtKB | Rhea| CHEBI:29108 )
Mg2+ (UniProtKB | Rhea| CHEBI:18420 )
Note: Mn2+ is the preferred divalent cation for ATP hydrolysis, but considerable activity is also detected in the presence of Ca2+ and Mg2+.
Activity regulation
Archaeal, but not bacterial, lipids stimulate the ATPase activity 3-4-fold.
pH Dependence
Optimum pH is 6.5 for ATP hydrolysis.
Temperature Dependence
Optimum temperature is 75 degrees Celsius for ATP hydrolysis.
Features
Showing features for binding site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 239 | ADP (UniProtKB | ChEBI) | ||||
Sequence: T | ||||||
Binding site | 265 | ADP (UniProtKB | ChEBI) | ||||
Sequence: A | ||||||
Binding site | 267 | ADP (UniProtKB | ChEBI) | ||||
Sequence: G | ||||||
Binding site | 268 | ADP (UniProtKB | ChEBI) | ||||
Sequence: K | ||||||
Binding site | 269 | ADP (UniProtKB | ChEBI) | ||||
Sequence: T | ||||||
Binding site | 269 | Mg2+ (UniProtKB | ChEBI) | ||||
Sequence: T | ||||||
Binding site | 270 | ADP (UniProtKB | ChEBI) | ||||
Sequence: T |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | archaeal-type flagellum | |
Cellular Component | plasma membrane | |
Molecular Function | ATP binding | |
Molecular Function | hydrolase activity | |
Molecular Function | metal ion binding |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameArchaeal flagellar ATPase motor FlaI
- EC number
Gene names
Organism names
- Strain
- Taxonomic lineageArchaea > Thermoproteota > Thermoprotei > Sulfolobales > Sulfolobaceae > Sulfolobus
Accessions
- Primary accessionQ4J9L0
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
Cell membrane ; Peripheral membrane protein
Note: Localizes to the membrane via a three-helix bundle domain (amino acids 61-127) present in the N-terminal region of FlaI.
Keywords
- Cellular component
Phenotypes & Variants
Disruption phenotype
The deletion mutant lacks flagella and is non-motile.
Features
Showing features for mutagenesis.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Mutagenesis | 69 | Significantly reduces localization to the membrane; when associated with E-72 and E-76. | ||||
Sequence: M → E | ||||||
Mutagenesis | 72 | Significantly reduces localization to the membrane; when associated with E-69 and E-76. | ||||
Sequence: I → E | ||||||
Mutagenesis | 76 | Significantly reduces localization to the membrane; when associated with E-69 and E-72. | ||||
Sequence: F → E | ||||||
Mutagenesis | 190 | Does not affect ATPase activity. Shows a reduced ability to form hexamers upon ATP binding; when associated with A-336. | ||||
Sequence: N → E | ||||||
Mutagenesis | 268 | 50% decrease in ATP hydrolysis. Decreases ATP binding. Cannot form oligomers. Can complement a deletion mutant. | ||||
Sequence: K → A | ||||||
Mutagenesis | 284 | Does not affect ATPase activity. Shows a reduced ability to form hexamers upon ATP binding; when associated with A-336. | ||||
Sequence: K → E | ||||||
Mutagenesis | 290 | Does not affect ATP hydrolysis and ATP binding. | ||||
Sequence: D → A | ||||||
Mutagenesis | 307 | Does not affect ATPase activity. Shows a reduced ability to form hexamers upon ATP binding; when associated with A-336. | ||||
Sequence: R → K | ||||||
Mutagenesis | 336 | Retains very low ATPase activity. Cannot restore archaellum assembly or swimming in a deletion mutant. Does not affect ATP binding. Forms a stable oligomer after ATP binding. Shows a reduced ability to form hexamers upon ATP binding; when associated with E-190; E-284 or K-307. | ||||
Sequence: E → A |
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000460734 | 1-513 | Archaeal flagellar ATPase motor FlaI | |||
Sequence: MSFVEDYLTKLQERPTIIENPNILKGSKIFNAIYRVDDFVYIHIQSIKSEDGYNQYNVIEPPRPTHDEMEEIEEKFALSIGDKEPPEDTKEKEKLIRSILDKILLRMRLSVPKEYVIYHFIRDKLYTGSLEPLIRDPYIEDISIPGLGHVYIVHKVFGPMRTSIKFENYEELDNLIVSLSEKSYRPVSHNRPVVDASLPDGSRVNFVYGVDISRRGSNLTVRKFSRVPTSITQLIMFGTLSSMMAAYIWTMLDEGMNLFVCGETASGKTTTLNAITAFIPPNLKIVTIEDTPELTVPHSNWVAEVTRETGGEGTIKLFDLLKAALRQRPNYILVGEIRDKEGNVAFQAMQTGHSVMATFHAANITTLIQRLTGYPIEVPKSYINNLNIALFQTALYDKKGNLIRRVVEVDEIIDIDPVTNDVVYIPAFTYDSVQDKMLFAGKGSSYLIENKIAVKRGIDRRNIGLLYDELQMRSRFLNLLVEKKIFNYYDVWDYILRARQMGLEEAIKYVSNI |
Interaction
Subunit
The S.acidocaldarius archaellum assembly machinery and its filament consist of seven proteins (FlaB, FlaF, FlaG, FlaH, FlaI, FlaJ and FlaX) (PubMed:22081969).
FlaI forms hexameric rings in the presence of ATP (PubMed:21506936, PubMed:23416110).
Interacts directly with the FlaX ring and FlaH (PubMed:23129770, PubMed:24103130, PubMed:26508112).
FlaI forms hexameric rings in the presence of ATP (PubMed:21506936, PubMed:23416110).
Interacts directly with the FlaX ring and FlaH (PubMed:23129770, PubMed:24103130, PubMed:26508112).
Binary interactions
Type | Entry 1 | Entry 2 | Number of experiments | Intact | |
---|---|---|---|---|---|
BINARY | Q4J9L0 | Saci_1177 Q4J9K6 | 5 | EBI-8759747, EBI-8759763 |
Protein-protein interaction databases
Structure
Family & Domains
Domain
Contains a variable N-terminal domain (NTD) and a conserved C-terminal ATPase domain (CTD), connected by a flexible linker (PubMed:23416110).
Both NTD and CTD form similarly sized globular structures (PubMed:23416110).
The NTD is essential for archaellum formation, motility and FlaI localization, but not for ATPase activity (PubMed:23416110).
ATP binding induces a conformational change and locks the hexamer into a more symmetrical and less dynamic conformation, which may promote hexamer assembly by stabilizing interactions across adjacent subunits (PubMed:23416110).
Both NTD and CTD form similarly sized globular structures (PubMed:23416110).
The NTD is essential for archaellum formation, motility and FlaI localization, but not for ATPase activity (PubMed:23416110).
ATP binding induces a conformational change and locks the hexamer into a more symmetrical and less dynamic conformation, which may promote hexamer assembly by stabilizing interactions across adjacent subunits (PubMed:23416110).
Sequence similarities
Belongs to the GSP E family.
Phylogenomic databases
Family and domain databases
Sequence
- Sequence statusComplete
- Length513
- Mass (Da)58,766
- Last updated2005-08-02 v1
- Checksum33D701376865F40B
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
CP000077 EMBL· GenBank· DDBJ | AAY80520.1 EMBL· GenBank· DDBJ | Genomic DNA |