Family C39


Summary Holotypes Alignment Tree Genomes Structure Literature

Summary for family C39

Family type peptidaseC39.001 - bacteriocin-processing peptidase (Pediococcus acidilactici), MEROPS Accession MER0002036 (peptidase unit: 1-150)
Content of familyPeptidase family C39 contains bacteriocin-processing endopeptidases from bacteria.
History Identifier created: Proteolysis in Cell Function, pp13-21, IOS Press, Amsterdam (1997)
The family has been reviewed by Jack et al. (2004) and Dirix et al. (2004). .
Catalytic typeCysteine
Active site residuesQ13 C19 H98 D,E118 
Active siteCatalytic residues have been identified as Cys19 and His98 (numbering as in the Alignment) in C39.005 (Wu & Tai, 2004). There is a conserved Gln six positions N-terminal to Cys19, which would align with the Gln that contributes to the oxyanion hole in families C2, C10 and others in clan CA.
Activities and specificitiesThe peptidases in family C39 cleave the 'double-glycine' leader peptides from the precursors of various bacteriocins (see Biological Functions). The cleavage is mediated by the transporter as part of the secretion process. Colicin V processing peptidase (C39.005) requires calcium and a thiol compound such as DTT for activity (Wu & Tai, 2004).
InhibitorsColicin V processing peptidase (C39.005) is inhibited by antipain, N-ethylmaleimide, <#J29.001#>EDTA and EGTA (Wu & Tai, 2004).
Molecular structureThe bacteriocin transporters are integral membrane proteins containing an N-terminal peptidase domain followed by six or more transmembrane domains and a C-terminal ATP-binding domain. The non-peptidase domains are homologous to a variety of other ABC transport proteins.
Basis of clan assignmentPredicted active site residues for members of this family and family C1 occur in the same order in the sequence: Q, C, H, D/N
Distribution of family Bacteria details  
Archaea details  
Protozoa details  
Fungi -  
Plants details  
Animals details  
Viruses details  
Biological functionsBacteriocins are antibiotic proteins secreted by some species of bacteria that inhibit the growth of other bacterial species. The bacteriocin is synthesized as a precursor with an N-terminal leader peptide, and processing involves removal of the leader peptide by cleavage at a Gly-Gly bond, followed by translocation of the mature bacteriocin across the cytoplasmic membrane. The endopeptidases of family C39 serve both functions, and the proteins are known as ATP-binding cassette transporters (ABC transporters).
Statistics for family C39Sequences:3682
Identifiers with PDB entries:1
Downloadable files Sequence library (FastA format)
Sequence alignment (FastA format)
Phylogenetic tree (Newick format)
Peptidases and Homologues MEROPS ID Structure
bacteriocin-processing peptidaseC39.001Yes
streptococcin processing peptidaseC39.003-
mersacidin lantibiotic processing peptidaseC39.004-
colicin V processing peptidaseC39.005-
mutacin II processing peptidase (Streptococcus mutans) and similarC39.006-
lacticin 481 processing peptidase (Lactococcus lactis)C39.007-
NukT peptidase (Staphylococcus warneri)C39.008-
sublancin 168 lantibiotic transporter (Bacillus subtilis)C39.A03-
family C39 non-peptidase homologuesnon-peptidase homologue-
family C39 unassigned peptidasesunassigned-