Glucooligosaccharides comprising (alpha 1->4) and (alpha 1->6) glycosidic bonds, use thereof, and methods for providing them

Patent metadata

Field	Value
Publication number	US-9657322-B2
Application number	US-201013319237-A
Country	US
Kind code	B2
Filing date	May 10, 2010
Priority date	May 8, 2009
Publication date	May 23, 2017
Grant date	May 23, 2017

Abstract

The invention relates to the field of poly-and oligosaccharides and their nutritional effects. In particular, it relates to the application of α-glucanotransferases in methods for preparing dietary fibers, including prebiotic oligosaccharides, and to novel oligosaccharides obtainable thereby. Provided is a method for producing a mixture of gluco-oligosaccharides having one or more consecutive (α1→6) glucosidic linkages and one or more consecutive (α1→4) glucosidic linkages, comprising contacting a poly- and/or oligosaccharide substrate comprising at least two (α1→4) linked D-glucose units with an α-glucanotransferase capable of cleaving (α1→4) glucosidic linkages and making new (α1→4) and (α1→6) glucosidic linkages. Also provided are (isolated) gluco-oligosaccharides obtainable thereby, and their application in nutritional and cosmetic compositions.

First claim

The invention claimed is:

1. A method for producing a mixture of gluco-oligosaccharides having one or more consecutive (α1→6) glucosidic linkages and one or more consecutive (α1→4) glucosidic linkages, comprising contacting a poly- and/or oligosaccharide substrate comprising at its non-reducing end at least two α1→4-linked D-glucose units with an α-glucanotransferase enzyme capable of cleaving (α1→4) glucosidic linkages and making new (α1→4) and (α1→6) glucosidic linkages, wherein said α-glucanotransferase enzyme comprises a polypeptide sequence having at least 60% identity to the catalytic core of α-glucanotransferase enzyme GTFB from Lactobacillus reuteri 121(SEQ ID NO. 59), wherein the α-glucanotransferase does not introduce (α1→6) branching points.

2. The method according to claim 1 , wherein said α-glucanotransferase does not introduce (α1→6) branching points nor (α1→2) or (α1→3) linkages.

3. The method according to claim 1 , wherein said α-glucanotransferase is from the GH70 glycoside hydrolase family.

4. The method according to claim 1 , wherein said α-glucanotransferase is selected from the group consisting of GTFB from Lactobacillus reuteri 121(SEQ ID NO. 59), GTF106B from Lactobacillus reuteri TMW 1.106(SEQ ID NO. 61), GTML4 from Lactobacillus reuteri ML1 (SEQ ID NO. 63), GTFDSM from Lactobacillus reuteri DSM 20016 A (SEQ ID NO. 65), and GTF from Lactobacillus fermentum ATCC 14931 (SEQ ID NO. 67).

5. The method according to claim 1 , wherein said substrate has a degree of polymerization of at least 4.

6. Method according to claim 1 , wherein said substrate is selected from the group consisting of starch, waxy starch, high amylose starch, their derivatives, malto-oligosaccharides, amylose, amylopectin, maltodextrins, (α1→4) glucans, reuteran, or combinations thereof.

7. Method according to claim 6 , wherein said starch, waxy starch, high amylose starch or starch derivative is derived from potato, maize, tapioca, pea, mung bean, rice or wheat.

8. Method according to claim 6 , wherein said starch derivative is produced by treating starch, waxy starch or high amylose starch with amylomaltase/4-alpha-glucanotransferase or glycogen -branching enzyme.

9. The method according to claim 1 , further comprising the step of isolating from the mixture at least one gluco-oligosaccharides having one or more consecutive (α1→6) glucosidic linkages and one or more consecutive (α1→4) glucosidic linkages.

10. The method according to claim 9 , wherein said isolation comprises at least one of precipitation-fractionation and chromatography.

11. The method according to claim 1 , wherein said α-glucanotransferase enzyme comprises at least one conserved amino acid residue selected from the group consisting of Asp1015, Glu1053, and Asp1125 of GTFB of Lactobacillus reuteri 121(SEQ ID NO. 59), and equivalent residues in-homologous α-glucanotransferase enzymes selected from the group consisting of GTF106B from Lactobacillus reuteri TMW 1.106(SEQ ID NO. 61), GTML4 from Lactobacillus reuteri ML1 (SEQ ID NO. 63), GTFDSM from Lactobacillus reuteri DSM 20016 A (SEQ ID NO. 65), and GTF from Lactobacillus fermentum ATCC 14931 (SEQ ID NO. 67).

12. The method according to claim 1 , wherein said substrate has a degree of polymerization of at least 6.

13. The method according to claim 1 , wherein said α-glucanotransferase enzyme comprises at least three conserved amino acid residues selected from the group consisting of Arg1013, Asp1015, Ala1017, Asn1019, Glu1053, Gly1054, Tyr1055, His1124, Asp1125, Gln1126, Arg1127, Lys1128, Asp1479, lle1480, Met1482, Asn1483, and Gln1484 of GTFB of Lactobacillus reuteri 121 (SEQ ID NO. 59), and equivalent residues in homologous α-glucanotransferase enzymes selected from the group consisting of GTF106B from Lactobacillus reuteri TMW 1.106(SEQ ID NO. 61), GTML4 from Lactobacillus reuteri ML1 (SEQ ID NO. 63), GTFDSM from Lactobacillus reuteri DSM 20016 A (SEQ ID NO. 65), and GTF from Lactobacillus fermentum ATCC 14931 (SEQ ID NO. 67).

14. The method according to claim 1 , wherein said α-glucanotransferase enzyme comprises Asp1015, Glu1053, and Asp1125 of GTFB of Lactobacillus reuteri 121(SEQ ID NO. 59), or equivalent residues in homologous α-glucanotransferase enzymes selected from the group consisting of GTF106B from Lactobacillus reuteri TMW 1.106(SEQ ID NO. 61), GTML4 from Lactobacillus reuteri ML1 (SEQ ID NO. 63), GTFDSM from Lactobacillus reuteri DSM 20016 A (SEQ ID NO. 65), and GTF from Lactobacillus fermentum ATCC 14931 (SEQ ID NO. 67).

15. The method according to claim 1 , wherein said α-glucanotransferase enzyme comprises Arg1013, Asp1015, Ala1017, Asn1019, Glu1053, Gly1054, Tyr1055, His1124, Asp1125, Gln1126, Arg1127, Lys1128, Asp1479, Ile1480, Met1482, Asn1483, and Gln1484 of GTFB of Lactobacillus reuteri 121(SEQ ID NO. 59); or equivalent residues in homologous α-glucanotransferase enzymes selected from the group consisting of GTF106B from Lactobacillus reuteri TMW 1.106(SEQ ID NO. 61), GTML4 from Lactobacillus reuteri ML1 (SEQ ID NO. 63), GTFDSM from Lactobacillus reuteri DSM 20016 A (SEQ ID NO. 65), and GTF from Lactobacillus fermentum ATCC 14931 (SEQ ID NO. 67).

16. The method according to claim 1 , wherein the catalytic core of GTFB from Lactobacillus reuteri 121 comprises SEQ ID NO. 60.

17. A method for producing starch derivatives or partially indigestible starch derivatives comprising contacting an enzyme capable of cleaving (α1→4) glucosidic linkages and making new (α1→4) and (α1→6) glucosidic linkages, and/or transferring a maltose, maltotriose or maltotetraosyl-unit making a new (α1→6) glucosidic linkage with a sequence having at least 60% identity to the catalytic core of an α-glucanotransferase enzyme selected from the group consisting of GTFB from Lactobacillus reuteri 121(SEQ ID NO. 59).

Assignees

• Dijkhuizen Lubbert
• Van Der Maarel Marc Jos Elise Cornelis
• Kamerling Johannis Paulus
• Leemhuis Reinder Johannes
• Kralj Slavko
• Dobruchowska Justyna Malgorzata
• Univ Groningen

Inventors

• Dijkhuizen Lubbert
• Van Der Maarel Marc Jos Elise Cornelis
• Kamerling Johannis Paulus
• Leemhuis Reinder Johannes
• Kralj Slavko
• Dobruchowska Justyna Malgorzata

Classifications

• C12Y204/01005

  Dextransucrase (2.4.1.5) · CPC title

• C12N9/1051

  Hexosyltransferases (2.4.1) · CPC title

• C12P19/04

  Polysaccharides, i.e. compounds containing more than five saccharide radicals attached to each other by glycosidic bonds · CPC title

• A61P3/02

  Nutrients, e.g. vitamins, minerals · CPC title

• C12P19/00 Primary

  Preparation of compounds containing saccharide radicals (ketoaldonic acids C12P7/58) · CPC title