Peptidase S26A, signal peptidase I (IPR000223)

Short name: Pept_S26A_signal_pept_1

Overlapping homologous superfamilies

Family relationships


This group of serine peptidases belong to MEROPS peptidase family S26 (signal peptidase I family, clan SF), subfamily S26A.

At least 3 eubacterial leader peptidases are known: murein prelipoprotein peptidase, which cleaves the leader peptide from a component of the bacterial outer membrane; type IV prepilin leader peptidase; and the serine-dependent leader peptidase 1, which has the more general role of cleaving the leader peptide from a variety of secreted proteins and proteins directed to the periplasm and periplasmic membrane [PMID: 7845208]. Leader peptidase 1 is similar to the eukaryotic signal peptidase, although the bacterial protein is monomeric, while the eukaryotic protein is multimeric [PMID: 7845208].

Mitochondria contain a similar two-subunit serine protease that removes leader peptides from nuclear- and mitochondrial-encoded proteins, which localise in the inner mitochondrial space [PMID: 7845208]. The catalytic residues of a number of these peptides have been identified as a serine/lysine dyad [PMID: 7845208].

GO terms

Biological Process

GO:0006508 proteolysis

Molecular Function

GO:0008236 serine-type peptidase activity

Cellular Component

GO:0016020 membrane

Contributing signatures

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