Q8DNS0 · STKP_STRR6

Function

function

Protein kinase involved in signal transduction pathways that regulate various cellular processes. Likely senses intracellular peptidoglycan subunits present in the cell division septa of actively growing cells; thus, intracellular unlinked peptidoglycan may serve as the signal molecules that trigger StkP phosphorylation activity on a set of substrates. Plays a crucial role in the regulation of cell shape and cell division of S.pneumoniae through control of at least DivIVA activity. Identified target substrates that are specifically phosphorylated by StkP in vivo, mainly on threonine residues, are DivIVA, KhpB (also called EloR/Jag) and StkP itself. Autophosphorylated StkP is a substrate for the cotranscribed protein phosphatase PhpP (shown in the avirulent strain Rx / Cp1015); PhpP and StkP appear to constitute a functional signaling couple in vivo.

Catalytic activity

Features

Showing features for binding site, active site.

TypeIDPosition(s)Description
Binding site18-26ATP (UniProtKB | ChEBI)
Binding site42ATP (UniProtKB | ChEBI)
Active site136Proton acceptor

GO annotations

AspectTerm
Cellular Componentplasma membrane
Molecular FunctionATP binding
Molecular Functionprotein kinase binding
Molecular Functionprotein serine kinase activity
Molecular Functionprotein serine/threonine kinase activity
Biological Processdivision septum assembly
Biological Processregulation of autophagy
Biological Processregulation of cell shape
Biological Processsignal transduction

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    Serine/threonine-protein kinase StkP
  • EC number
  • Short names
    Ser/Thr-protein kinase StkP
  • Alternative names
    • Eukaryotic-type Ser/Thr protein kinase (ESTPK)

Gene names

    • Name
      stkP
    • Synonyms
      pkn2
    • Ordered locus names
      spr1577

Organism names

Accessions

  • Primary accession
    Q8DNS0

Proteomes

Subcellular Location

Cell membrane
; Single-pass membrane protein
Note: The kinase domain is located intracellularly, while the C-terminal PASTA domain is exposed extracellularly. Localizes to the midcell division sites. Time-lapse microscopy shows that StkP displays an intermediate timing of recruitment to midcell: StkP arrives shortly after FtsA but before DivIVA. Furthermore, StkP remains at midcell longer than FtsA, until division is complete. Delocalizes from the septum in the presence of antibiotics that target the latest stages of cell-wall biosynthesis and in cells that have stopped dividing.

Features

Showing features for topological domain, transmembrane.

TypeIDPosition(s)Description
Topological domain1-342Cytoplasmic
Transmembrane343-363Helical
Topological domain364-659Extracellular

Keywords

Phenotypes & Variants

Disruption phenotype

According to PubMed:22211696, cells lacking this gene show round shape (the cell shape of wild-type strain is ovoid) and form long chains with unsplit cross-wall joining cells. Their septa either are not positioned at the equator, or display an aberrant ultrastructure (curly aspects). They display delocalized sites of peptidoglycan synthesis. According to PubMed:22431591, cells in which StkP is depleted clearly show an elongated phenotype, with cell-wall synthesis occurring along the peripheral side between the septal zones. Reduces transcription of the peptidoglycan hydrolase pcsB gene (PubMed:27902439).

Features

Showing features for mutagenesis.

TypeIDPosition(s)Description
Mutagenesis42Cells form very elongated and unchained cells. They have a giant length size and show the aberrant presence of multiple septa that do not seem functional. StkP is properly recruited to each non-constricted septum site. No phosphorylation activity. Slight reduction in transcription of the peptidoglycan hydrolase pcsB gene, but less than effect of deletion mutant.

PTM/Processing

Features

Showing features for chain.

TypeIDPosition(s)Description
ChainPRO_00004181461-659Serine/threonine-protein kinase StkP

Post-translational modification

Autophosphorylation occurs predominantly at the threonine residue and weakly at the serine residue. Dephosphorylated by PhpP (By similarity).

Keywords

Interaction

Subunit

Homodimer. StkP forms dimers through its transmembrane and extracellular domains. Dimer formation likely promotes autophosphorylation activity and might be necessary for targeting StkP substrate (By similarity).
Interacts with MreC in the elongasome (PubMed:28710862).
May interact with sensor histidine kinase WalK, thereby playing a role in signal transduction by WalK

Protein-protein interaction databases

Family & Domains

Features

Showing features for domain, region.

TypeIDPosition(s)Description
Domain12-273Protein kinase
Domain366-433PASTA 1
Domain434-505PASTA 2
Domain506-577PASTA 3
Region541-561Disordered
Domain578-651PASTA 4

Domain

Consists of an N-terminal kinase domain, a transmembrane domain, and a C-terminal domain containing four repeats of the PASTA signature sequence (Penicillin-binding protein and Ser/Thr protein kinase associated domain). The PASTA domain binds to peptidoglycan (PGN) subunits (shown in strain Rx / Cp1015), is essential for StkP activation and substrate phosphorylation, and is required for cellular targeting to midcell.

Sequence similarities

Belongs to the protein kinase superfamily. Ser/Thr protein kinase family.

Keywords

Phylogenomic databases

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    659
  • Mass (Da)
    72,293
  • Last updated
    2003-03-01 v1
  • Checksum
    A469FB99617B1586
MIQIGKIFAGRYRIVKQIGRGGMADVYLAKDLILDGEEVAVKVLRTNYQTDPIAVARFQREARAMADLDHPHIVRITDIGEEDGQQYLAMEYVAGLDLKRYIKEHYPLSNEEAVRIMGQILLAMRLAHTRGIVHRDLKPQNILLTPDGTAKVTDFGIAVAFAETSLTQTNSMLGSVHYLSPEQARGSKATVQSDIYAMGIIFYEMLTGHIPYDGDSAVTIALQHFQNPLPSVIAENSSVPQALENVIIKATAKKLTNRYRSVSEMYVDLSSSLSYNRRNESKLIFDETSKADTKTLPKVSQSTLTSIPKVQAQTEHKSIKNPSQAVTEETYQPQAPKKHRFKMRYLILLASLVLVAASLIWILSRTPATIAIPDVAGQTVAEAKATLKKANFEIGEEKTEASEKVEEGRIIRTDPGAGTGRKEGTKINLVVSSGKQSFQISNYVGRKSSDVIAELKEKKVPDNLIKIEEEESNESEAGTVLKQSLPEGTTYDLSKATQIVLTVAKKATTIQLGNYIGRNSTEVISELKQKKVPENLIKIEEEESSESEPGTIMKQSPGAGTTYDVSKPTQIVLTVAKKVTSVAMPSYIGSSLEFTKNNLIQIVGIKEANIEVVEVTTAPAGSVEGMVVEQSPRAGEKVDLNKTRVKISIYKPKTTSATP

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
AE007317
EMBL· GenBank· DDBJ
AAL00380.1
EMBL· GenBank· DDBJ
Genomic DNA

Genome annotation databases

Similar Proteins

Disclaimer

Any medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care. Our staff consists of biologists and biochemists that are not trained to give medical advice.
We'd like to inform you that we have updated our Privacy Notice to comply with Europe’s new General Data Protection Regulation (GDPR) that applies since 25 May 2018.
FeedbackHelp