Homologous Superfamily

Trigger factor/SurA domain superfamily (IPR027304)

Short name: Trigger_fact/SurA_dom_sf

Overlapping entries


The C-terminal domain of trigger factor and the peptide-binding domain of porin chaperone SurA share a multi-helical structure consisting of an irregular array of long and short helices.

In the Escherichia coli cytosol, a fraction of the newly synthesised proteins requires the activity of molecular chaperones for folding to the native state. The major chaperones implicated in this folding process are the ribosome-associated Trigger Factor (TF), and the DnaK and GroEL chaperones with their respective co-chaperones. Trigger Factor is an ATP-independent chaperone and displays chaperone and peptidyl-prolyl-cis-trans-isomerase (PPIase) activities in vitro. It is composed of at least three domains, an N-terminal domain which mediates association with the large ribosomal subunit, a central substrate binding and PPIase domain with homology to FKBP proteins, and a C-terminal domain of unknown function. The positioning of TF at the peptide exit channel, together with its ability to interact with nascent chains as short as 57 residues renders TF a prime candidate for being the first chaperone that binds to the nascent polypeptide chains [PMID: 12603737].

The porin chaperon SurA facilitates correct folding of outer membrane proteins in Gram-negative bacteria [PMID: 12429090].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.