Q4J9L0 · FLAI_SULAC

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).

Catalytic activity

Cofactor

Mn2+ (UniProtKB | Rhea| CHEBI:29035 )

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.

TypeIDPosition(s)Description
Binding site239ADP (UniProtKB | ChEBI)
Binding site265ADP (UniProtKB | ChEBI)
Binding site267ADP (UniProtKB | ChEBI)
Binding site268ADP (UniProtKB | ChEBI)
Binding site269ADP (UniProtKB | ChEBI)
Binding site269Mg2+ (UniProtKB | ChEBI)
Binding site270ADP (UniProtKB | ChEBI)

GO annotations

AspectTerm
Cellular Componentarchaeal-type flagellum
Cellular Componentplasma membrane
Molecular FunctionATP binding
Molecular Functionhydrolase activity
Molecular Functionmetal ion binding

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    Archaeal flagellar ATPase motor FlaI
  • EC number

Gene names

    • Name
      flaI
    • Ordered locus names
      Saci_1173

Organism names

Accessions

  • Primary accession
    Q4J9L0

Proteomes

Subcellular Location

Archaeal flagellum
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

Phenotypes & Variants

Disruption phenotype

The deletion mutant lacks flagella and is non-motile.

Features

Showing features for mutagenesis.

TypeIDPosition(s)Description
Mutagenesis69Significantly reduces localization to the membrane; when associated with E-72 and E-76.
Mutagenesis72Significantly reduces localization to the membrane; when associated with E-69 and E-76.
Mutagenesis76Significantly reduces localization to the membrane; when associated with E-69 and E-72.
Mutagenesis190Does not affect ATPase activity. Shows a reduced ability to form hexamers upon ATP binding; when associated with A-336.
Mutagenesis26850% decrease in ATP hydrolysis. Decreases ATP binding. Cannot form oligomers. Can complement a deletion mutant.
Mutagenesis284Does not affect ATPase activity. Shows a reduced ability to form hexamers upon ATP binding; when associated with A-336.
Mutagenesis290Does not affect ATP hydrolysis and ATP binding.
Mutagenesis307Does not affect ATPase activity. Shows a reduced ability to form hexamers upon ATP binding; when associated with A-336.
Mutagenesis336Retains 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.

PTM/Processing

Features

Showing features for chain.

TypeIDPosition(s)Description
ChainPRO_00004607341-513Archaeal flagellar ATPase motor FlaI

Expression

Induction

Part of the fla operon, which encodes the seven fla genes essential for crenarchaeal flagellum assembly and function (PubMed:22081969).
Expression is induced by tryptone starvation (PubMed:22081969).

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).

Binary interactions

TypeEntry 1Entry 2Number of experimentsIntact
BINARY Q4J9L0Saci_1177 Q4J9K65EBI-8759747, EBI-8759763

Protein-protein interaction databases

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).

Sequence similarities

Belongs to the GSP E family.

Phylogenomic databases

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    513
  • Mass (Da)
    58,766
  • Last updated
    2005-08-02 v1
  • Checksum
    33D701376865F40B
MSFVEDYLTKLQERPTIIENPNILKGSKIFNAIYRVDDFVYIHIQSIKSEDGYNQYNVIEPPRPTHDEMEEIEEKFALSIGDKEPPEDTKEKEKLIRSILDKILLRMRLSVPKEYVIYHFIRDKLYTGSLEPLIRDPYIEDISIPGLGHVYIVHKVFGPMRTSIKFENYEELDNLIVSLSEKSYRPVSHNRPVVDASLPDGSRVNFVYGVDISRRGSNLTVRKFSRVPTSITQLIMFGTLSSMMAAYIWTMLDEGMNLFVCGETASGKTTTLNAITAFIPPNLKIVTIEDTPELTVPHSNWVAEVTRETGGEGTIKLFDLLKAALRQRPNYILVGEIRDKEGNVAFQAMQTGHSVMATFHAANITTLIQRLTGYPIEVPKSYINNLNIALFQTALYDKKGNLIRRVVEVDEIIDIDPVTNDVVYIPAFTYDSVQDKMLFAGKGSSYLIENKIAVKRGIDRRNIGLLYDELQMRSRFLNLLVEKKIFNYYDVWDYILRARQMGLEEAIKYVSNI

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
CP000077
EMBL· GenBank· DDBJ
AAY80520.1
EMBL· GenBank· DDBJ
Genomic DNA

Genome annotation databases

Similar Proteins

Disclaimer

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