Protein Domain : Phage tail collar domain superfamily IPR037053

Type	Homologous_superfamily
Description	This entry represents a domain superfamily found in Bacteriophage T4, Gp12. The characteristics of the protein distribution suggest prophage matches in addition to the phage matches.This region is occasionally found in conjunction with . Most of the proteins appear to be phage tail proteins; however some appear to be involved in other processes. For instance the RhiB protein ( ) from Rhizobium leguminosarum may be involved in plant-microbe interactions [ ]. A related protein, microcystin related protein (MrpB, ) is involved in the pathogenicity of Microcystis aeruginosa. The finding of this family in a structural component of the phage tail fibre baseplate ( ) suggests that its function is structural rather than enzymatic. Structural studies show this region consists of a helix and a loop [ ] and three β-strands. This alignment does not catch the third strand as it is separated from the rest of the structure by around 100 residues. This strand is conserved in homologues but the intervening sequence is not. Much of the function of appears to reside in this intervening region. In the tertiary structure of the phage baseplate this domain forms part of the collar and may bind SO 4. The long unconserved region maybe due to domain swapping in and out of a loop or due to rapid evolution.
Short Name	Phage_tail_collar_dom_sf