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1314  structures 9324  species 0  interactions 607278  sequences 16819  architectures

Clan: His_Kinase_A (CL0025)


His Kinase A (phospho-acceptor) domain Add an annotation

This is the dimerisation and phospho-acceptor domain of a sub-family of histidine kinases. It shares sequence similarity with Pfam:PF00512 and Pfam:PF07536. It is usually found adjacent to a C-terminal ATPase domain (Pfam:PF02518). This domain is found in a wide range of Bacteria and also several Archaea. It comprises one of the fundamental units of the two-component signal transduction system [2-7].

This clan contains 11 families and the total number of domains in the clan is 607278. The clan was built by DJ Studholme.

Literature references

  1. Grebe TW, Stock JB; , Adv Microb Physiol 1999;41:139-227.: The histidine protein kinase superfamily. PUBMED:10500846 EPMC:10500846
  2. Hwang I, Chen HC, Sheen J; , Plant Physiol 2002;129:500-515.: Two-component signal transduction pathways in Arabidopsis. PUBMED:12068096 EPMC:12068096
  3. Lohrmann J, Harter K; , Plant Physiol 2002;128:363-369.: Plant two-component signaling systems and the role of response regulators. PUBMED:11842140 EPMC:11842140
  4. Santos JL, Shiozaki K; , Sci STKE 2001;2001:RE1.: Fungal histidine kinases. PUBMED:11752677 EPMC:11752677
  5. West AH, Stock AM; , Trends Biochem Sci 2001;26:369-376.: Histidine kinases and response regulator proteins in two-component signaling systems. PUBMED:11406410 EPMC:11406410
  6. Rodrigue A, Quentin Y, Lazdunski A, Mejean V, Foglino M; , Trends Microbiol 2000;8:498-504.: Two-component systems in Pseudomonas aeruginosa: why so many?. PUBMED:11121759 EPMC:11121759
  7. Stock AM, Robinson VL, Goudreau PN; , Annu Rev Biochem 2000;69:183-215.: Two-component signal transduction. PUBMED:10966457 EPMC:10966457


This clan contains the following 11 member families:

H-kinase_dim HATPase_c HATPase_c_2 HATPase_c_3 HATPase_c_4 HATPase_c_5 HisKA HisKA_2 HisKA_3 HPTransfase HWE_HK

External database links

Domain organisation

Below is a listing of the unique domain organisations or architectures from this clan. More...

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The table below shows the number of occurrences of each domain throughout the sequence database. More...

Pfam family Num. domains Alignment
HATPase_c (PF02518) 300774 (49.5%) View
HisKA (PF00512) 188697 (31.1%) View
HisKA_3 (PF07730) 42435 (7.0%) View
HATPase_c_2 (PF13581) 27413 (4.5%) View
HATPase_c_3 (PF13589) 22546 (3.7%) View
HisKA_2 (PF07568) 6292 (1.0%) View
H-kinase_dim (PF02895) 5921 (1.0%) View
HWE_HK (PF07536) 4330 (0.7%) View
HATPase_c_5 (PF14501) 4178 (0.7%) View
HATPase_c_4 (PF13749) 3579 (0.6%) View
HPTransfase (PF10090) 1113 (0.2%) View
Total: 11 Total: 607278 Clan alignment

Please note: Clan alignments can be very large and can cause problems for some browsers. Read the note above before viewing.

Family relationships

This diagram shows the relationships between members of this clan. More...

Species distribution

Tree controls


This tree shows the occurrence of the domains in this clan across different species. More...



For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the MSD group, to allow us to map Pfam domains onto UniProt three-dimensional structures. The table below shows the mapping between the Pfam families in this clan, the corresponding UniProt entries, and the region of the three-dimensional structures that are available for that sequence.

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