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22  structures 608  species 0  interactions 1567  sequences 74  architectures

Family: Alginate_lyase2 (PF08787)

Summary: Alginate lyase

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This is the Wikipedia entry entitled "Poly(beta-D-mannuronate) lyase". More...

Poly(beta-D-mannuronate) lyase Edit Wikipedia article

poly(beta-D-mannuronate) lyase
EC number4.2.2.3
CAS number9024-15-1
IntEnzIntEnz view
ExPASyNiceZyme view
MetaCycmetabolic pathway
PDB structuresRCSB PDB PDBe PDBsum
Gene OntologyAmiGO / QuickGO
PDB 1vav EBI.jpg
crystal structure of alginate lyase pa1167 from pseudomonas aeruginosa at 2.0 a resolution

In enzymology, a poly(beta-D-mannuronate) lyase (EC is an enzyme that catalyzes the chemical reaction

Eliminative cleavage of polysaccharides containing beta-D-mannuronate residues to give oligosaccharides with 4-deoxy-alpha-L-erythro-hex-4-enopyranuronosyl groups at their ends

This enzyme belongs to the family of lyases, specifically those carbon-oxygen lyases acting on polysaccharides. The systematic name of this enzyme class is poly(beta-D-1,4-mannuronide) lyase. Other names in common use include alginate lyase I, alginate lyase, alginase I, alginase II, and alginase. This enzyme participates in fructose and mannose metabolism.

Structural studies

As of late 2007, 3 structures have been solved for this class of enzymes, with PDB accession codes 1HV6, 1J1T, and 2CWS.


  • Davidson IW, Lawson CJ, Sutherland IW (1977). "An alginate lysate from Azotobacter vinelandii phage". J. Gen. Microbiol. 98 (1): 223–9. doi:10.1099/00221287-98-1-223. PMID 13144.
  • Nakada HI, Sweeny PC (1967). "Alginic acid degradation by eliminases from abalone hepatopancreas". J. Biol. Chem. 242 (5): 845–51. PMID 6020438.
  • Preiss J; Ashwell G (1962). "Alginic acid metabolism in bacteria. I. Enzymatic formation of unsaturated oligosaccharides and 4-deoxy-L-erythro-5-hexoseulose uronic acid". J. Biol. Chem. 237: 309–316.

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.

Alginate lyase Provide feedback

Alginate lyases are enzymes that degrade the linear polysaccharide alignate. They cleave the glycosidic linkage of alignate through a beta-elimination reaction. This family forms an all beta fold and is different to all alpha fold of PF05426.

Internal database links

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR014895

Alginate lyases are enzymes that degrade the linear polysaccharide alignate. They cleave the glycosidic linkage of alignate through a beta-elimination reaction. This region forms an all beta fold, which is different to the all alpha fold of INTERPRO .

Domain organisation

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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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Seed source: pdb_1uai
Previous IDs: none
Type: Domain
Sequence Ontology: SO:0000417
Author: Mistry J
Number in seed: 66
Number in full: 1567
Average length of the domain: 215.40 aa
Average identity of full alignment: 23 %
Average coverage of the sequence by the domain: 70.39 %

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 30.0 29.7
Noise cut-off 29.2 29.5
Model length: 236
Family (HMM) version: 13
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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 Alginate_lyase2 domain has been found. There are 22 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
K7KLJ9 View 3D Structure Click here
K7KV50 View 3D Structure Click here
Q2QX37 View 3D Structure Click here
Q2QX80 View 3D Structure Click here