Q8DPL8 · WALK_STRR6
- ProteinSensor histidine protein kinase/phosphatase WalK
- GenewalK
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids449 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Member of the two-component regulatory system WalK/WalR that regulates genes involved in cell wall metabolism (By similarity).
Functions as a sensor protein kinase which is autophosphorylated at a histidine residue and transfers its phosphate group to WalR (PubMed:20190050, PubMed:23013245).
In turn, WalR binds to the upstream promoter regions of target genes to positively and negatively regulate their expression (By similarity).
Required to maintain expression of WalRK regulon genes in exponentially growing cells, including peptidoglycan hydrolase pcsB (PubMed:27902439).
Phosphorylates WalR and also capable of dephosphorylation of WalR (PubMed:20190050, PubMed:23013245, PubMed:27902439).
WalK phosphatase activity is probably involved in preventing cross-talk from PnpS and other non-cognate sensor kinases during exponential growth (By similarity).
Functions as a sensor protein kinase which is autophosphorylated at a histidine residue and transfers its phosphate group to WalR (PubMed:20190050, PubMed:23013245).
In turn, WalR binds to the upstream promoter regions of target genes to positively and negatively regulate their expression (By similarity).
Required to maintain expression of WalRK regulon genes in exponentially growing cells, including peptidoglycan hydrolase pcsB (PubMed:27902439).
Phosphorylates WalR and also capable of dephosphorylation of WalR (PubMed:20190050, PubMed:23013245, PubMed:27902439).
WalK phosphatase activity is probably involved in preventing cross-talk from PnpS and other non-cognate sensor kinases during exponential growth (By similarity).
Catalytic activity
Activity regulation
Autophosphorylation is decreased in vitro by dithiothreitol (DTT), perhaps because of disruption of disulfide bond formation and covalent dimerization.
Kinetics
KM | SUBSTRATE | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|---|
42 μM | ATP | 7.8 | 25 |
Kinetic parameters were determined with a truncated form of WalK, which includes only the cytoplasmic domain and not the short extracellular domain and the transmembrane region. kcat is 0.08 sec-1 for ATP (at pH 7.8 and 25 degrees Celsius).
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | membrane | |
Molecular Function | hydrolase activity | |
Molecular Function | phosphorelay response regulator activity | |
Molecular Function | phosphorelay sensor kinase activity | |
Molecular Function | protein kinase activator activity | |
Molecular Function | protein kinase binding | |
Biological Process | osmosensory signaling via phosphorelay pathway | |
Biological Process | regulation of DNA-templated transcription | |
Biological Process | signal transduction |
Keywords
- Molecular function
- Biological process
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameSensor histidine protein kinase/phosphatase WalK
- EC number
Gene names
Organism names
- Strain
- Taxonomic lineageBacteria > Bacillota > Bacilli > Lactobacillales > Streptococcaceae > Streptococcus
Accessions
- Primary accessionQ8DPL8
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
Membrane ; Single-pass type III membrane protein
Features
Showing features for topological domain, transmembrane.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Topological domain | 1-13 | Extracellular | ||||
Sequence: MLDLLKQTIFTRD | ||||||
Transmembrane | 14-34 | Helical | ||||
Sequence: FIFILILLGFILVVTLLLLEN | ||||||
Topological domain | 35-449 | Cytoplasmic | ||||
Sequence: RRDNIQLKQINQKVKDLIAGDYSKVLDMQGGSEITNITNNLNDLSEVIRLTQENLEQESKRLNSILFYMTDGVLATNRRGQIIMINDTAKKQLGLVKEDVLNRSILELLKIEENYELRDLITQSPELLLDSQDINGEYLNLRVRFALIRRESGFISGLVAVLHDTTEQEKEERERRLFVSNVSHELRTPLTSVKSYLEALDEGALCETVAPDFIKVSLDETNRMMRMVTDLLHLSRIDNATSHLDVELINFTAFITFILNRFDKMKGQEKEKKYELVRDYPINSIWMEIDTDKMTQVVDNILNNAIKYSPDGGKITVRMKTTEDQMILSISDHGLGIPKQDLPRIFDRFYRVDRARSRAQGGTGLGLSIAKEIIKQHKGFIWAKSEYGKGSTFTIVLPYDKDAVKEEVWEDEVED |
Keywords
- Cellular component
Phenotypes & Variants
Disruption phenotype
Almost abolishes transcription of the peptidoglycan hydrolase pcsB gene; similar phenotype with simultaneous deletion of serine/threonine-protein kinase stkP (PubMed:27902439).
Simultaneous deletion of response regulator pnpR increases transcription of pcsB; similar phenotype when combined with simultaneous deletion of stkP (PubMed:27902439).
Simultaneous deletion of response regulator pnpR increases transcription of pcsB; similar phenotype when combined with simultaneous deletion of stkP (PubMed:27902439).
Features
Showing features for mutagenesis.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Mutagenesis | 1-35 | Retains autophosphorylation. | ||||
Sequence: Missing | ||||||
Mutagenesis | 1-195 | Retains autophosphorylation. | ||||
Sequence: Missing | ||||||
Mutagenesis | 12-37 | Increases transcription of the peptidoglycan hydrolase pcsB gene. | ||||
Sequence: RDFIFILILLGFILVVTLLLLENRRD → AAFIFILILLGFILVVTLLLLENRAA | ||||||
Mutagenesis | 22 | Reduces transcription of the peptidoglycan hydrolase pcsB gene. | ||||
Sequence: G → A | ||||||
Mutagenesis | 23 | Reduces transcription of the peptidoglycan hydrolase pcsB gene. Does not negatively affect WalK expression or membrane insertion. | ||||
Sequence: F → A | ||||||
Mutagenesis | 33 | Reduces transcription of the peptidoglycan hydrolase pcsB gene. | ||||
Sequence: E → A | ||||||
Mutagenesis | 33-34 | Reduces transcription of the peptidoglycan hydrolase pcsB gene. | ||||
Sequence: EN → AA | ||||||
Mutagenesis | 36-37 | Reduces transcription of the peptidoglycan hydrolase pcsB gene. | ||||
Sequence: RD → AA | ||||||
Mutagenesis | 104-198 | Reduces autophosphorylation. Reduces phosphatase activity. | ||||
Sequence: Missing | ||||||
Mutagenesis | 133-140 | No effect on autophosphorylation. | ||||
Sequence: DVLNRSIL → NVLYRSIR | ||||||
Mutagenesis | 216 | Severely reduces autophosphorylation. | ||||
Sequence: V → G | ||||||
Mutagenesis | 217 | Severely reduces autophosphorylation. | ||||
Sequence: S → D | ||||||
Mutagenesis | 218 | Abolishes autophosphorylation. Reduces phosphatase activity by about 12-fold. | ||||
Sequence: H → A | ||||||
Mutagenesis | 221 | Severely reduces autophosphorylation. | ||||
Sequence: R → D | ||||||
Mutagenesis | 222 | Greatly reduces phosphatase activity. Increases transcription of the peptidoglycan hydrolase pcsB gene; simultaneous deletion of serine/threonine kinase stkP has no effect. | ||||
Sequence: T → A | ||||||
Mutagenesis | 222 | Severely reduces autophosphorylation. | ||||
Sequence: T → D | ||||||
Mutagenesis | 222 | Reduces autophosphorylation. Reduces phosphatase activity by about 12-fold. | ||||
Sequence: T → R | ||||||
Mutagenesis | 223 | Severely reduces autophosphorylation. | ||||
Sequence: P → A | ||||||
Mutagenesis | 223 | Severely reduces autophosphorylation. | ||||
Sequence: P → S |
PTM/Processing
Features
Showing features for chain, modified residue.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000458748 | 1-449 | Sensor histidine protein kinase/phosphatase WalK | |||
Sequence: MLDLLKQTIFTRDFIFILILLGFILVVTLLLLENRRDNIQLKQINQKVKDLIAGDYSKVLDMQGGSEITNITNNLNDLSEVIRLTQENLEQESKRLNSILFYMTDGVLATNRRGQIIMINDTAKKQLGLVKEDVLNRSILELLKIEENYELRDLITQSPELLLDSQDINGEYLNLRVRFALIRRESGFISGLVAVLHDTTEQEKEERERRLFVSNVSHELRTPLTSVKSYLEALDEGALCETVAPDFIKVSLDETNRMMRMVTDLLHLSRIDNATSHLDVELINFTAFITFILNRFDKMKGQEKEKKYELVRDYPINSIWMEIDTDKMTQVVDNILNNAIKYSPDGGKITVRMKTTEDQMILSISDHGLGIPKQDLPRIFDRFYRVDRARSRAQGGTGLGLSIAKEIIKQHKGFIWAKSEYGKGSTFTIVLPYDKDAVKEEVWEDEVED | ||||||
Modified residue | 218 | Phosphohistidine; by autocatalysis | ||||
Sequence: H |
Post-translational modification
Autophosphorylated.
Keywords
- PTM
PTM databases
Structure
Family & Domains
Features
Showing features for domain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Domain | 35-87 | HAMP | ||||
Sequence: RRDNIQLKQINQKVKDLIAGDYSKVLDMQGGSEITNITNNLNDLSEVIRLTQE | ||||||
Domain | 92-158 | PAS | ||||
Sequence: ESKRLNSILFYMTDGVLATNRRGQIIMINDTAKKQLGLVKEDVLNRSILELLKIEENYELRDLITQS | ||||||
Domain | 157-211 | PAC | ||||
Sequence: QSPELLLDSQDINGEYLNLRVRFALIRRESGFISGLVAVLHDTTEQEKEERERRL | ||||||
Domain | 215-435 | Histidine kinase | ||||
Sequence: NVSHELRTPLTSVKSYLEALDEGALCETVAPDFIKVSLDETNRMMRMVTDLLHLSRIDNATSHLDVELINFTAFITFILNRFDKMKGQEKEKKYELVRDYPINSIWMEIDTDKMTQVVDNILNNAIKYSPDGGKITVRMKTTEDQMILSISDHGLGIPKQDLPRIFDRFYRVDRARSRAQGGTGLGLSIAKEIIKQHKGFIWAKSEYGKGSTFTIVLPYDK |
Domain
Transmembrane domain is involved in signal sensing or transduction.
PAS domain is involved in phosphatase activity.
Keywords
- Domain
Phylogenomic databases
Family and domain databases
Sequence
- Sequence statusComplete
- Length449
- Mass (Da)51,712
- Last updated2003-03-01 v1
- Checksum852DDD120B4E87D3
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
AE007317 EMBL· GenBank· DDBJ | AAK99909.1 EMBL· GenBank· DDBJ | Genomic DNA |