Ulvan lyases isolated from the Flavobacteria Persicivirga ulvanivorans are the first members of a new polysaccharide lyase family.
Ulvans are complex sulfated polysaccharides found in the cell walls of green algae belonging to the genus Ulva. These polysaccharides are composed of disaccharide repetition moieties made up of sulfated rhamnose linked to either glucuronic acid, iduronic acid, or xylose. Two ulvan lyases of 30 and 46 kDa were purified from the culture supernatant of Persicivirga ulvanivorans. Based on peptide sequencing, the gene encoding the 46-kDa ulvan lyase was cloned. Sequence analysis revealed that the protein is modular and possesses a catalytic module similar to that of the 30-kDa ulvan lyase along with a module of unknown function. The ulvan-degrading function of the gene was confirmed by expression of the catalytic module in a heterologous system. The gene encoding the catalytic module has no sequence homolog in sequence databases and is likely to be the first member of a novel polysaccharide lyase family. Analysis of degradation products showed that both the 30- and 46-kDa ulvan lyases are endolytic and cleave the glycosidic bond between the sulfated rhamnose and a glucuronic or iduronic acid.
CNRS, Université Pierre et Marie Curie-Paris 6, Unité Mixte de Recherche 7139 "Marine Plants and Biomolecules," Station Biologique, F-29682 Roscoff Cedex, France.
Pi
P
Nyvall Collén
Centre d'Etudes et de Valorisation des Algues, Presqu'île de Pen Lan, BP3, 22610 Pleubian, France.
Jean-François
JF
Sassi
UR1268 Biopolymères Interactions Assemblages, Institut National de la Recherche Agronomique, Plate-forme Biopolymères Biologie Structurale, Rue de la Géraudière, BP 71627, 44316 Nantes, France.
Hélène
H
Rogniaux
Centre d'Etudes et de Valorisation des Algues, Presqu'île de Pen Lan, BP3, 22610 Pleubian, France.
Hélène
H
Marfaing
CNRS, Université Pierre et Marie Curie-Paris 6, Unité Mixte de Recherche 7139 "Marine Plants and Biomolecules," Station Biologique, F-29682 Roscoff Cedex, France. Electronic address: helbert@sb-roscoff.fr.
William
W
Helbert
D000595:Amino Acid Sequence; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002473:Cell Wall / Q000378:metabolism*; D000460:Chlorophyta / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D002853:Chromatography, Liquid / Q000379:methods; D003001:Cloning, Molecular; D004798:Enzymes / Q000737:chemistry; D020723:Glucuronic Acid / Q000737:chemistry; D007067:Iduronic Acid / Q000737:chemistry; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry; D011133:Polysaccharide-Lyases / Q000737:chemistry; D053719:Tandem Mass Spectrometry / Q000379:methods; D044445:Ulva / Q000737:chemistry*
D004798:Enzymes; D010455:Peptides; D007067:Iduronic Acid; D020723:Glucuronic Acid; D011133:Polysaccharide-Lyases