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180  structures 8  species 0  interactions 14  sequences 4  architectures

Family: Peptidase_M27 (PF01742)

Summary: Clostridial neurotoxin zinc protease

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Clostridial neurotoxin zinc protease Provide feedback

These toxins are zinc proteases that block neurotransmitter release by proteolytic cleavage of synaptic proteins such as synaptobrevins, syntaxin and SNAP-25.

Literature references

  1. Montecucco C, Schiavo G, Tugnoli V, de Grandis D; , Mol Med Today 1996;2:418-424.: Botulinum neurotoxins: mechanism of action and therapeutic applications. PUBMED:8897436 EPMC:8897436

  2. Montecucco C, Schiavo G; , Trends Biochem Sci 1993;18:324-327.: Tetanus and botulism neurotoxins: a new group of zinc proteases. PUBMED:7901925 EPMC:7901925

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR000395

The Clostridium neurotoxin family is composed of tetanus neurotoxin (TeNT) and seven serotypes of botulinum neurotoxin (BoNT). It also includes the Botulinum non-toxic non-hemagglutinin (NTNHA) component, which forms a binary complex with BoNT to protect it from gastrointestinal degradation [ PUBMED:26363288 ]. These toxins act as inhibitors of neurotransmitter release [ PUBMED:1328520 , PUBMED:23435179 ]. They are zinc proteases that block neurotransmitter release by proteolytic cleavage of synaptic proteins such as synaptobrevins, syntaxin and SNAP-25 [ PUBMED:8897436 , PUBMED:7901925 ].

BoNT and TeNT are di-chain proteins linked by an interchain disulfide bond. They are comprised of an N-terminal catalytic light chain (LC), and a C-terminal heavy chain (HC) that consists of a translocation domain (HCT) and a receptor-binding domain (HCR). Through the translocation domain LC is translocated and delivered into the host cytosol [ PUBMED:25895970 ].

This entry represents LC, the catalytic light chain.

Gene Ontology

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Domain organisation

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We store a range of different sequence alignments for families. As well as the seed alignment from which the family is built, we provide the full alignment, generated by searching the sequence database (reference proteomes) using the family HMM. We also generate alignments using four representative proteomes (RP) sets and the UniProtKB sequence database. More...

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We make a range of alignments for each Pfam-A family. You can see a description of each above. You can view these alignments in various ways but please note that some types of alignment are never generated while others may not be available for all families, most commonly because the alignments are too large to handle.

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Representative proteomes UniProt

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You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.

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This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.

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Curation and family details

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Curation View help on the curation process

Seed source: Pfam-B_407 (release 4.2)
Previous IDs: none
Type: Family
Sequence Ontology: SO:0100021
Author: Bateman A
Number in seed: 2
Number in full: 14
Average length of the domain: 380.1 aa
Average identity of full alignment: 32 %
Average coverage of the sequence by the domain: 32.66 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 61295632 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 27.0 27.0
Trusted cut-off 43.6 43.0
Noise cut-off 26.0 18.9
Model length: 417
Family (HMM) version: 20
Download: download the raw HMM for this family

Species distribution

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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the Peptidase_M27 domain has been found. There are 180 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.

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AlphaFold Structure Predictions

The list of proteins below match this family and have AlphaFold predicted structures. Click on the protein accession to view the predicted structure.

Protein Predicted structure External Information
P04958 View 3D Structure Click here
P0DPI1 View 3D Structure Click here