Centre National De La Recherche Scientifique

Institut National De La Recherche Agronomique

Institut National Des Sciences Appliquees De Toulouse

Institut National De Recherche Pour L'agriculture, L'alimentation Et L'environnement

Universitë De Bordeaux

Institut Polytechnique De Bordeaux

Institut National Des Sciences Appliquees Toulouse

Institut Pasteur

Université Paul Sabatier (Toulouse III)

Centre National De La Recherche Scientifique-Cnrs

Institut National Des Sciences Appiquees De Toulouse (Insat)

Pierre Monsan

Claire Moulis

Magali Remaud-Simeon

Gabrielle Potocki-Veronese

Marlene Vuillemin

Isabelle Andre

Sandrine Morel

Marlène Vuillemin

Marion Claverie

Pierre F Monsan

Laurence Mulard

Stéphane Grelier

Sophie Barbe

Frédéric Peruch

Etienne Severac

Guillaume Le Heiget

Zhaohu Hu

Louis-Antoine Barel

Mounir Benkoulouche

Akli Ben Imeddourene

Catherine Fontagne-Faucher

Patrick Lucas

Marguerite Dols-Lafargue

Catherine Garnier

Agnès Sabate

Florent Grimaud

Alvaro Lafraya

David Guieysse

The present invention provides protected tetrasaccharides, their process of preparation and their use in the synthesis of oligosaccharides, in particular fragments of O-antigens from, for example of serotype 1a, 1b, 2a, 2b, 3a, X, 4a, 4b, 5a, 5b, 7a or 7b.

Protected tetrasaccharides, their process of preparation and their use as transglucosylase acceptor substrates in the chemo-enzymatic synthesis ofspecific oligosaccharides

Polypeptides having the ability to specifically form connections of glucosyl units in alpha 1,3 on an acceptor having at least one hydroxyl moiety are presented. The polypeptides include i) the pattern I of sequence SEQ ID NO: 1, ii) the pattern II of sequence SEQ ID NO: 2, iii) the pattern III of sequence SEQ ID NO: 3, and iv) the pattern IV of sequence SEQ ID NO: 4, or derivates from one or several of said patterns, wherein the polypeptide furthermore has an aspartic residue (D) at position 5 of the pattern II (SEQ ID NO: 2), a glutamic acid residue (E) at position 6 of the pattern III (SEQ ID NO: 3) an an aspartic acid residue (D) at position 6 of the pattern IV (SEQ ID NO: 4). Methods for producing acceptors connected to glucosyl units in alpha 1,3 using the polypeptides are also provided.

Polypeptide having the ability to form connections of glucosyl units in alpha-1,3 on an acceptor

Polypeptides having the ability to specifically form connections of glucosyl units in alpha 1,3 on an acceptor having at least one hydroxyl moiety are presented. The polypeptides include i) the pattern I of sequence SEQ ID NO: 1, ii) the pattern II of sequence SEQ ID NO: 2, iii) the pattern III of sequence SEQ ID NO: 3, and iv) the pattern IV of sequence SEQ ID NO: 4, or derivates from one or several of said patterns, wherein the polypeptide furthermore has an aspartic residue (D) at position 5 of the pattern II (SEQ ID NO: 2), a glutamic acid residue (E) at position 6 of the pattern III (SEQ ID NO: 3) and an aspartic acid residue (D) at position 6 of the pattern IV (SEQ ID NO: 4). Methods for producing acceptors connected to glucosyl units in alpha 1,3 using the polypeptides are also provided.

Polypeptide having the capacity to form alpha-1,3 glucosyl unit branchings on an acceptor

The present invention relates to a method for producing a glycosylated synthon or a monomer. Said method includes at least one step of placing at least one glycan-saccharase in the presence of at least one hydroxylated synthon and at least one saccharose. The invention also relates to a method for producing a glyco(co)polymer, including polymerizing at least two monomers separately obtained from the enzymatic glycosylation method according to the invention, and to a method for producing a glyco(co)polymer, preferably a block glyco(co)polymer, including coupling at least two monomers separately obtained from the enzymatic glycosylation method according to the invention.

Enzymatic production of glycosylated synthons

The invention relates to: &#x2014;a protein having dextran-saccharase activity and the sequence SEQ ID NO: 1 for an amino acid sequence; &#x2014;a protein having dextran-saccharase activity and the sequence SEQ ID NO: 2 for an amino acid sequence; &#x2014;a complex containing a substrate and a protein with dextran-saccharase activity &#x2014;a method for synthesizing dextrans; and &#x2014;dextrans. The invention also relates to a method for synthesizing gluco-oligosaccharides and gluco-conjugates and to the resulting products.

Protein with dextran-saccharase activity, and uses

The subject matter of the invention is dextrans which have between 95% and 99% of &#x3b1;-1,6 glucosidic bonds, a weight-average molar mass Mat least equal to 0.7&#xd7;10g.mol, and a dispersity index D of between 1.3 and 3. The invention also relates to a dextran saccharase which makes it possible to produce such dextrans, and to a method for producing said dextrans.

Very high molar mass dextrans

The present invention relates to a recombinant process for the production of truncated or mutated dextransucrases while conserving the enzymatic activity or their specificity in the synthesis of the &#x3b1;-1,6 bonds. The present invention relates to nucleic acid sequences of truncated or mutated dextransucrases, vectors containing the nucleic acid sequences and host cells transformed by sequences encoding truncated or mutated dextransucrases. In another aspect, the invention concerns a method for producing, in a recombinant manner, truncated or mutated dextransucrases which conserve their enzymatic activity or which conserve their specificity in the synthesis of &#x3b1;-1,6 bonds and can produce, from saccharose, dextrans with high molar mass and modified rheological properties compared with the properties of dextran obtained with the native enzyme and isomalto-oligosaccharides with a controlled molar mass and dextrans. The dextrans and isomalto-oligosaccharides of the invention can be used namely as texturing agents or as prebiotics.

Construction of new variants of dextransucrase DSR-S by genetic engineering

Growing community of inventors

Garidech, France

Claire Moulis