Reaction: Eliminative cleavage of alginate to give oligosaccharides with 4-deoxy-α-L-erythro-hex-4-enuronosyl groups at their non-reducing ends and β-D-mannuronate at their reducing end.
Other name(s): alginate lyase I; alginate lyase; alginase I; alginase II; alginase; poly(β-D-1,4-mannuronide) lyase; poly(β-D-mannuronate) lyase; aly (gene name) (ambiguous); poly[(1→4)-β-D-mannuronide] lyase
Systematic name: alginate β-D-mannuronate—uronate lyase
Comments: The enzyme catalyses the degradation of alginate by a β-elimination reaction. It cleaves the (1→4) bond between β-D-mannuronate and either α-L-guluronate or β-D-mannuronate, generating oligosaccharides with 4-deoxy-α-L-erythro-hex-4-enuronosyl groups at their non-reducing ends and β-D-mannuronate at the reducing end. Depending on the composition of the substrate, the enzyme produces oligosaccharides ranging from two to four residues, with preference for shorter products. cf. EC 4.2.2.11, guluronate-specific alginate lyase.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9024-15-1
References:
1. Davidson, I.W., Lawson, C.J. and Sutherland, I.W. An alginate lysate from Azotobacter vinelandii phage. J. Gen. Microbiol. 98 (1977) 223-229. [PMID: 13144]
2. Nakada, H.I. and Sweeny, P.C. Alginic acid degradation by eliminases from abalone hepatopancreas. J. Biol. Chem. 242 (1967) 845-851. [PMID: 6020438]
3. Preiss, J. and Ashwell, G. Alginic acid metabolism in bacteria. I. Enzymatic formation of unsaturated oligosaccharides and 4-deoxy-L-erythro-5-hexoseulose uronic acid. J. Biol. Chem. 237 (1962) 309-316. [PMID: 14488584]