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13  structures 721  species 0  interactions 1503  sequences 4  architectures

Clan: YycI_YycH (CL0285)


YycI/YycH superfamily Add an annotation

Both, YycH and YycI are always found in a pair on the chromosome, downstream of the essential histidine kinase YycG. Additionally, both proteins share a function in regulating the YycG kinase with which they appear to form a ternary complex. Structural studies show that these two protein families share two related domains.

This clan contains 2 families and the total number of domains in the clan is 1503. The clan was built by A Bateman.

Literature references

  1. Santelli E, Liddington RC, Mohan MA, Hoch JA, Szurmant H; , J Bacteriol. 2007;189:3290-3295.: The crystal structure of Bacillus subtilis YycI reveals a common fold for two members of an unusual class of sensor histidine kinase regulatory proteins. PUBMED:17307848 EPMC:17307848


This clan contains the following 2 member families:

YycH YycI

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
YycI (PF09648) 787 (52.4%) View
YycH (PF07435) 716 (47.6%) View
Total: 2 Total: 1503 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.

Loading structure mapping...