Please note: this site relies heavily on the use of javascript. Without a javascript-enabled browser, this site will not function correctly. Please enable javascript and reload the page, or switch to a different browser.
0  structures 775  species 0  interactions 2921  sequences 89  architectures

Family: Chitin_synth_1 (PF01644)

Summary: Chitin synthase

Pfam includes annotations and additional family information from a range of different sources. These sources can be accessed via the tabs below.

This is the Wikipedia entry entitled "Chitin synthase". More...

Chitin synthase Edit Wikipedia article

chitin synthase
EC number2.4.1.16
CAS number9030-18-6
IntEnzIntEnz view
ExPASyNiceZyme view
MetaCycmetabolic pathway
PDB structuresRCSB PDB PDBe PDBsum
Gene OntologyAmiGO / QuickGO

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

UDP-N-acetyl-D-glucosamine + [1,4-(N-acetyl-beta-D-glucosaminyl)]n UDP + [1,4-(N-acetyl-beta-D-glucosaminyl)]n+1

Thus, the two substrates of this enzyme are UDP-N-acetyl-D-glucosamine and [[[1,4-(N-acetyl-beta-D-glucosaminyl)]n]], whereas its two products are UDP and [[[1,4-(N-acetyl-beta-D-glucosaminyl)]n+1]].

This enzyme belongs to the family of glycosyltransferases, specifically the hexosyltransferases. The systematic name of this enzyme class is UDP-N-acetyl-D-glucosamine:chitin 4-beta-N-acetylglucosaminyl-transferase. Other names in common use include chitin-UDP N-acetylglucosaminyltransferase, chitin-uridine diphosphate acetylglucosaminyltransferase, chitin synthetase, and trans-N-acetylglucosaminosylase. This enzyme participates in aminosugars metabolism.


Chitin Synthase is manufactured in the rough endoplasmic reticulum of fungi as the inactive form, zymogen. The zymogen is then packaged into chitosomes in the golgi apparatus. Chitosomes bring the zymogen to the hyphal tip of a mold or yeast cell membrane. Chitin synthase is placed into the interior side of the cell membrane and then activated.[citation needed]


  • GLASER L, BROWN DH (1957). "The synthesis of chitin in cell-free extracts of Neurospora crassa". J. Biol. Chem. 228 (2): 729–42. PMID 13475355.
  • Sburlati A, Cabib E (1986). "Chitin synthetase 2, a presumptive participant in septum formation in Saccharomyces cerevisiae". J. Biol. Chem. 261 (32): 15147–52. PMID 2945823.

This page is based on a Wikipedia article. The text is available under the Creative Commons Attribution/Share-Alike License.

This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.

Chitin synthase Provide feedback

This region is found commonly in chitin synthases classes I, II and III. Chitin a linear homopolymer of GlcNAc residues, it is an important component of the cell wall of fungi and is synthesised on the cytoplasmic surface of the cell membrane by membrane bound chitin synthases [2].

Literature references

  1. Nino-Vega GA, Buurman ET, Gooday GW, San-Blas G, Gow NA; , Yeast 1998;14:181-187.: Molecular cloning and sequencing of a chitin synthase gene (CHS2) of Paracoccidioides brasiliensis. PUBMED:9483806 EPMC:9483806

  2. Georgopapadakou NH, Tkacz JS; , Trends Microbiol 1995;3:98-104.: The fungal cell wall as a drug target. PUBMED:7773595 EPMC:7773595

  3. Bowen AR, Chen-Wu JL, Momany M, Young R, Szaniszlo PJ, Robbins PW; , Proc Natl Acad Sci U S A 1992;89:519-523.: Classification of fungal chitin synthases. PUBMED:1731323 EPMC:1731323

Internal database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR004834

This region is found commonly in chitin synthases classes I, II and III EC . Chitin a linear homopolymer of GlcNAc residues, it is an important component of the cell wall of fungi and is synthesised on the cytoplasmic surface of the cell membrane by membrane bound chitin synthases [ PUBMED:7773595 ].

Gene Ontology

The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.

Domain organisation

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

Loading domain graphics...


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...

View options

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.

Representative proteomes UniProt
Jalview View  View  View  View  View  View  View 
HTML View  View           
PP/heatmap 1 View           

1Cannot generate PP/Heatmap alignments for seeds; no PP data available

Key: ✓ available, x not generated, not available.

Format an alignment

Representative proteomes UniProt

Download options

We make all of our alignments available in Stockholm format. You can download them here as raw, plain text files or as gzip-compressed files.

Representative proteomes UniProt
Raw Stockholm Download   Download   Download   Download   Download   Download   Download  
Gzipped Download   Download   Download   Download   Download   Download   Download  

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

HMM logo

HMM logos is one way of visualising profile HMMs. Logos provide a quick overview of the properties of an HMM in a graphical form. You can see a more detailed description of HMM logos and find out how you can interpret them here. More...


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.

Note: You can also download the data file for the tree.

Curation and family details

This section shows the detailed information about the Pfam family. You can see the definitions of many of the terms in this section in the glossary and a fuller explanation of the scoring system that we use in the scores section of the help pages.

Curation View help on the curation process

Seed source: Pfam-B_892 (release 4.1)
Previous IDs: Chitin_synth;
Type: Family
Sequence Ontology: SO:0100021
Author: Bashton M , Bateman A
Number in seed: 93
Number in full: 2921
Average length of the domain: 162.00 aa
Average identity of full alignment: 53 %
Average coverage of the sequence by the domain: 17.49 %

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 25.0 25.0
Trusted cut-off 26.2 25.3
Noise cut-off 24.7 24.8
Model length: 163
Family (HMM) version: 19
Download: download the raw HMM for this family

Species distribution

Sunburst controls


Weight segments by...

Change the size of the sunburst


Colour assignments

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


Align selected sequences to HMM

Generate a FASTA-format file

Clear selection

This visualisation provides a simple graphical representation of the distribution of this family across species. You can find the original interactive tree in the adjacent tab. More...

Loading sunburst data...

Tree controls


The tree shows the occurrence of this domain across different species. More...


Please note: for large trees this can take some time. While the tree is loading, you can safely switch away from this tab but if you browse away from the family page entirely, the tree will not be loaded.

AlphaFold Structure Predictions

trRosetta Structure

The structural model below was generated by the Baker group with the trRosetta software using the Pfam UniProt multiple sequence alignment.

The InterPro website shows the contact map for the Pfam SEED alignment. Hovering or clicking on a contact position will highlight its connection to other residues in the alignment, as well as on the 3D structure.

Improved protein structure prediction using predicted inter-residue orientations. Jianyi Yang, Ivan Anishchenko, Hahnbeom Park, Zhenling Peng, Sergey Ovchinnikov, David Baker Proceedings of the National Academy of Sciences Jan 2020, 117 (3) 1496-1503; DOI: 10.1073/pnas.1914677117;