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PROSITE documentation PDOC50885 [for PROSITE entry PS50885]

HAMP domain profile


The HAMP linker domain (domain present in Histidine kinases, Adenyl cyclases, Methyl-accepting proteins and Phosphatases) is an approximately 50-amino acid α-helical region common to chemoreceptors and histidine kinases that is present in several multidomain sensor proteins that participate in a variety of signal transduction processes. One or several copies of the HAMP domain can be found in association with other domains such as the histidine kinase domain (see <PDOC50109>), the bacterial chemotaxis sensory transducer domain (see <PDOC00465>), the PAS repeat (see <PDOC50112>), the EAL domain (see <PDOC50883>), the GGDEF domain (see <PDOC50887>), the protein phosphatase 2C-like domain, the guanylate cyclase domain (see <PDOC00425>), or the response regulatory domain (see <PDOC50110>). It has been suggested that the HAMP domain possesses a role of regulating the phosphorylation or methylation of homodimeric receptors by transmitting the conformational changes in periplasmic ligand-binding domains to cytoplasmic signalling kinase and methyl-acceptor domains [1].

Some proteins known to contain a HAMP domain are listed below:

  • Anabaena cylindrica adenylate cyclase. It may function as a membrane- localized receptor protein.
  • Escherichia coli osmolarity sensor protein envZ. It functions as a membrane-associated protein kinase that phosphorylates ompR in response to environmental signals.
  • Escherichia coli sensor protein barA. It could activate ompR by phosphorylation.
  • Escherichia coli nitrate/nitrite sensor protein narX. It probably activates narL and narP by phosphorylation in the presence of nitrate.
  • Escherichia coli sensor protein cpxA.
  • Escherichia coli methyl-accepting chemotaxis protein I.
  • Escherichia coli hypothetical protein yfiN.
  • Escherichia coli protein yhjK.
  • Rhizobium sp. strain NGR234 probable chemoreceptor Y4FA.
  • Salmonella typhimurium methyl-accepting chemotaxis protein II.
  • Chlamydia trachomatis sigma regulatory family protein-PP2C phosphatase.
  • Treponema pallidum hypothetical protein TP0854.
  • Synechocystis sp. strain PCC 6803 pleD.
  • Synechocystis sp. strain PCC 6803 hypothetical protein sll1365.
  • Archaeoglobus fulgidus putative signal-transducing histidine kinase.
  • Archaeoglobus fulgidus hypothetical protein AF1503.
  • Halobacterium salinarium halobacterial transducer protein IV.
  • Yeast osmolarity two-component system protein SLN1.
  • Candida albicans protein NIK1.

The profile we developed covers the entire HAMP domain.

Last update:

December 2002 / First entry.

Technical section

PROSITE method (with tools and information) covered by this documentation:

HAMP, PS50885; HAMP domain profile  (MATRIX)


1AuthorsAravind L., Ponting C.P.
TitleThe cytoplasmic helical linker domain of receptor histidine kinase and methyl-accepting proteins is common to many prokaryotic signalling proteins.
SourceFEMS Microbiol. Lett. 176:111-116(1999).
PubMed ID10418137

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