H-kinase_dim Signal transducing histidine kinase, homodimeric domain
SMART ACC:	SM001231
Description:	This helical bundle domain is the homodimer interface of the signal transducing histidine kinase family.
InterPro ACC:	IPR004105
InterPro abstract:	Signal transducing histidine kinases are the key elements in two-component signal transduction systems, which control complex processes such as the initiation of development in microorganisms [ PUBMED:8868347 PUBMED:11406410 ]. Examples of histidine … expand Signal transducing histidine kinases are the key elements in two-component signal transduction systems, which control complex processes such as the initiation of development in microorganisms [ PUBMED:8868347 PUBMED:11406410 ]. Examples of histidine kinases are EnvZ, which plays a central role in osmoregulation [ PUBMED:10426948 ], and CheA, which plays a central role in the chemotaxis system [ PUBMED:9989504 ]. Histidine kinases usually have an N-terminal ligand-binding domain and a C-terminal kinase domain, but other domains may also be present. The kinase domain is responsible for the autophosphorylation of the histidine with ATP, the phosphotransfer from the kinase to an aspartate of the response regulator, and (with bifunctional enzymes) the phosphotransfer from aspartyl phosphate back to ADP or to water [ PUBMED:11145881 ]. The kinase core has a unique fold, distinct from that of the Ser/Thr/Tyr kinase superfamily. This helical bundle domain is the homodimer interface of signal transducing histidine kinases like CheA [ PUBMED:9989504 ]. collapse
GO process:	phosphorelay signal transduction system (GO:0000160), chemotaxis (GO:0006935)
GO component:	cytoplasm (GO:0005737)
GO function:	phosphorelay sensor kinase activity (GO:0000155), protein histidine kinase activity (GO:0004673)
Family alignment:	View the Family alignment or the Alignment consensus sequence
There are 18 862 H-kinase_dim domains in 18 862 proteins in SMART's NRDB database.

Taxonomic distribution of proteins containing H-kinase_dim domains

The tree below includes only several representative species and genera. The complete taxonomic breakdown of all proteins containing H-kinase_dim domains can be accessed here. Click the counts or percentage values to display the corresponding proteins.

Predicted cellular role

Cellular role:	Signalling

Relevant references for this domain

Primary literature for the H-kinase_dim domain is listed below. Automatically-derived, secondary literature is also available.

KEGG pathways involving proteins which contain this domain

This information is based on the mapping of SMART genomic protein database to KEGG orthologous groups. Percentages are related to the number of proteins containing a H-kinase_dim domain which could be assigned to a KEGG orthologous group, and not all proteins containing H-kinase_dim domains. Please note that proteins can be included in multiple pathways, ie. the numbers below will not add to 100%.

KEGG pathways

Some of these pathways are included in the interactive Pathways Explorer overview maps. Select an overview map and click the button below to highlight them in iPath.

KEGG orthologous groups

Some of these KOs are included in the interactive Pathways Explorer overview maps. Select an overview map and click the button below to highlight them in iPath.

3D structures in PDB containing this domain

Links to other resources describing this domain

InterPro	IPR004105
Pfam	H-kinase_dim