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5  structures 3651  species 0  interactions 5485  sequences 74  architectures

Family: Creatinase_N_2 (PF16189)

Summary: Creatinase/Prolidase N-terminal domain

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This is the Wikipedia entry entitled "Creatinase". More...

Creatinase Edit Wikipedia article

EC number3.5.3.3
CAS number37340-58-2
IntEnzIntEnz view
ExPASyNiceZyme view
MetaCycmetabolic pathway
PDB structuresRCSB PDB PDBe PDBsum
Gene OntologyAmiGO / QuickGO
Creatinase/Prolidase N-terminal domain
The Crystal Structure of the Creatinase/Prolidase N-terminal domain of an X-PRO dipeptidase from Streptococcus pyogenes to 1.85A [1]

In enzymology, a creatinase (EC is an enzyme that catalyzes the chemical reaction

creatine + H2O sarcosine + urea

Thus, the two substrates of this enzyme are creatine and H2O, whereas its two products are sarcosine and urea.

The native enzyme was shown to be made up of two subunit monomers via SDS-polyacrylamide gel electrophoresis. The molecular weights of these subunits was estimated to be 47,000 g/mol.[2] The enzyme works as a homodimer, and is induced by choline chloride. Each monomer of creatinase has two clearly defined domains, a small N-terminal domain, and a large C-terminal domain. Each of the two active sites is made by residues of the large domain of one monomer and some residues of the small domain of the other monomer. It has been suggested that a sulfhydryl group is located on or near the active site of the enzyme following inhibition experiments.[2] Creatinase has been found to be most active at pH 8 and is most stable between ph 6-8 for 24 hrs. at 37 degrees.[2]

This enzyme belongs to the family of hydrolases, those acting on carbon-nitrogen bonds other than peptide bonds, specifically in linear amidines. The systematic name of this enzyme class is creatine amidinohydrolase. This enzyme participates in arginine and proline metabolism.

Structural studies

As of late 2007, two structures have been solved for this class of enzymes, with PDB accession codes 1CHM and 1KP0.


"RCSB Protein Data Bank - Structure Summary for 3O5V - The Crystal Structure of the Creatinase/Prolidase N-terminal domain of an X-PRO dipeptidase from Streptococcus pyogenes to 1.85A".

  1. ^ "RCSB Protein Data Bank - Structure Summary for 3O5V - The Crystal Structure of the Creatinase/Prolidase N-terminal domain of an X-PRO dipeptidase from Streptococcus pyogenes to 1.85A".
  2. ^ a b c Yoshimoto T, Oka I, Tsuru D (June 1976). "Purification, crystallization, and some properties of creatine amidinohydrolase from Pseudomonas putida". J. Biochem. 79 (6): 1381–3. PMID 8443.
  • ROCHE J, LACOMBE G, GIRARD H (1950). "[On the specificity of certain bacterial deguanidases generating urea and on arginindihydrolase.]". Biochim. Biophys. Acta. 6 (1): 210–6. doi:10.1016/0006-3002(50)90093-x. PMID 14791411.

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Creatinase/Prolidase N-terminal domain Provide feedback

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This tab holds annotation information from the InterPro database.

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Domain organisation

Below is a listing of the unique domain organisations or architectures in which this domain is found. More...

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Pfam Clan

This family is a member of clan AMP_N-like (CL0356), which has the following description:

Bacterial amino-peptidases and creatinases, where the fold is a ribonuclease H-like motif, are grouped in this superfamily.

The clan contains the following 4 members:

AMP_N Creatinase_N Creatinase_N_2 FACT-Spt16_Nlob


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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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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Seed source: Phmmer:Q9NQW7
Previous IDs: none
Type: Domain
Sequence Ontology: SO:0000417
Author: Coggill P
Number in seed: 557
Number in full: 5485
Average length of the domain: 163.20 aa
Average identity of full alignment: 30 %
Average coverage of the sequence by the domain: 25.89 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 57096847 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 29.7 29.7
Trusted cut-off 29.7 29.8
Noise cut-off 28.7 29.1
Model length: 161
Family (HMM) version: 7
Download: download the raw HMM for this family

Species distribution

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Archea Archea Eukaryota Eukaryota
Bacteria Bacteria Other sequences Other sequences
Viruses Viruses Unclassified Unclassified
Viroids Viroids Unclassified sequence Unclassified sequence


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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 Creatinase_N_2 domain has been found. There are 5 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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