Methods and kits for folding proteins

1. A method for folding protein comprising providing an aqueous solution of a protein in non-native conformation and an inulin or inulin derivative or a mixture of inulins and/or inulin derivatives and incubating the solution to permit folding of the protein, wherein the inulin or inulin derivative is a compound of formula (I):

G(O—CO—NH—R 1 ) a —[F(O—CO—NH—R 2 ) b ] n   (I)

wherein:

G is a terminal glucosyl unit in which one or more hydroxyl groups thereof may be substituted with a group or groups of formula(O—CO—NH—R 1 );

R 1 is selected from the group comprising alkyl groups, alkenyl groups, alkynyl groups, haloalkyl groups, cycloalkyl groups, aryl groups and aralkyl groups and, where there is more than one (O—CO—NH—R 1 ) group on the glucosyl unit, each R 1 group may be the same or different;

a is an integer of from 0 to 4;

F is a fructosyl unit in which one or more hydroxyl groups thereof may be substituted with a group or groups of formula (O—CO—NH—R 2 );

R 2 is selected from the group comprising alkyl groups, alkenyl groups, alkynyl groups, haloalkyl groups, cycloalkyl groups, aryl groups and aralkyl groups and, where there is more than one (O—CO—NH—R 2 ) group on the fructosyl unit, each R 2 group may be the same or different;

b is an integer of from 0 to 3 for non-terminal fructosyl units and from 0 to 4 for the terminal fructosyl unit;

n is an integer of from 2 to 499,

each unit of formula F(O—CO—NH—R 2 ) b may be the same or different from any other unit of formula F(O—CO—NH—R 2 ) b ; and

the average degree of substitution per glucosyl or fructosyl unit is from 0.01 to 3.0.

2. The method according to claim 1 , wherein the inulin or inulin derivative or the mixture of inulins and/or inulin derivatives is present at a concentration of from 0.005 mg/ml to 50 mg/ml.

3. The method according to claim 1 , wherein the inulin or inulin derivative or the mixture of inulins and/or inulin derivatives is present at a concentration of from 0.002 mg/ml to 20 mg/ml.

4. The method according to claim 1 , wherein incubation is performed at a temperature of from about 0° C. to about 45° C.

5. The method according to claim 1 further comprising removing the inulin or inulin derivative or the mixture of inulins and/or inulin derivatives by dilution, buffer exchange through dialysis, diafiltration, filtration, precipitation and/or a chromatographic method.

6. The method according to claim 5 wherein the inulin or inulin derivative or the mixture of inulins and/or inulin derivatives is removed during and/or after protein refolding.

7. The method according to claim 1 wherein one or more of a chitin, chitosan, cyclodextrin, cycloamylose, hydrophobic resin and/or hydrophobic gel is further included in the solution.

8. The method according to claim 7 , further comprising removal of one or more of the chitin, chitosan, cyclodextrin, cycloamylose, a hydrophobic resin and/or a hydrophobic gel from the solution during and/or after protein refolding.

9. The method according to claim 1 , wherein said method is preceded by using a chaotrope, detergent and/or reducing agent to denature protein and/or dissolve aggregated proteins and/or inclusion bodies to provide an aqueous solution of protein in non-native conformation.

10. The method according to claim 9 , wherein the concentration of chaotrope, detergent and/or reducing agent is reduced prior to, at the start of, or during the method for folding protein by dilution or buffer exchange through dialysis, diafiltration, filtration, precipitation and/or a chromatographic method.

11. The method according to claim 1 , wherein a disulphide shuffling agent is included in the folding solution.

12. The method according to claim 1 , wherein the inulin or inulin derivative compound of formula (I) is a polydisperse linear or slightly branched inulin N-alkylurethane.

13. A kit designed or suitable for performing a method according to claim 1 , comprising, in a container or containers, one or more inulin(s) and/or inulin derivative(s), together with instructions for use of the kit, wherein the one or more inulin(s) and/or inulin derivative(s) is a compound of formula (I):

G(O—CO—NH—R 1 ) a —[F(O—CO—NH—R 2 ) b ] n   (I)

wherein:

G is a terminal glucosyl unit in which one or more hydroxyl groups thereof may be substituted with a group or groups of formula (O—CO—NH—R 1 );

R 1 is selected from the group comprising alkyl groups, alkenyl groups, alkynyl groups, haloalkyl groups, cycloalkyl groups, aryl groups and aralkyl groups and, where there is more than one (O—CO—NH—R 1 ) group on the glucosyl unit, each R 1 group may be the same or different;

a is an integer of from 0 to 4;

F is a fructosyl unit in which one or more hydroxyl groups thereof may be substituted with a group or groups of formula (O—CO—NH—R 2 );

R 2 is selected from the group comprising alkyl groups, alkenyl groups, alkynyl groups, haloalkyl groups, cycloalkyl groups, aryl groups and aralkyl groups and, where there is more than one (O—CO—NH—R 2 ) group on the fructosyl unit, each R 2 group may be the same or different;

b is an integer of from 0 to 3 for non-terminal fructosyl units and from 0 to 4 for the terminal fructosyl unit;

n is an integer of from 2 to 499,

each unit of formula F(O—CO—NH—R 2 ) b may be the same or different from any other unit of formula F(O—CO—NH—R 2 ) b ; and

the average degree of substitution per glucosyl or fructosyl unit is from 0.01 to 3.0.

14. The kit according to claim 13 , wherein the inulin or inulin derivative compound of formula (I) is a polydisperse linear or slightly branched inulin N-alkylurethane.

15. The kit for performing a method according to claim 1 , comprising one or more inulin(s) and/or inulin derivative(s) in a first container or containers and one or more of a cyclodextrin, cycloamylose, chitin, chitosan, hydrophobic resin and/or hydrophobic gel in a second container or containers, optionally together with instructions for use of the kit, wherein the one or more inulin(s) and/or inulin derivative(s) is a compound of formula (I):

G(O—CO—NH—R 1 ) a —[F(O—CO—NH—R 2 ) b ] n   (I)

wherein:

G is a terminal glucosyl unit in which one or more hydroxyl groups thereof may be substituted with a group or groups of formula (O—CO—NH—R 1 );

R 1 is selected from the group comprising alkyl groups, alkenyl groups, alkynyl groups, haloalkyl groups, cycloalkyl groups, aryl groups and aralkyl groups and, where there is more than one (O—CO—NH—R 1 ) group on the glucosyl unit, each R 1 group may be the same or different; a is an integer of from 0 to 4;

F is a fructosyl unit in which one or more hydroxyl groups thereof may be substituted with a group or groups of formula (O—CO—NH—R 2 );

R 2 is selected from the group comprising alkyl groups, alkenyl groups, alkynyl groups, haloalkyl groups, cycloalkyl groups, aryl groups and aralkyl groups and, where there is more than one (O—CO—NH—R 2 ) group on the fructosyl unit, each R 2 group may be the same or different;

b is an integer of from 0 to 3 for non-terminal fructosyl units and from 0 to 4 for the terminal fructosyl unit;

n is an integer of from 2 to 499,

each unit of formula F(O—CO—NH—R 2 ) b may be the same or different from any other unit of formula F(O—CO—NH—R 2 ) b ; and

the average degree of substitution per glucosyl or fructosyl unit is from 0.01 to 3.0.

16. The method according to claim 1 , wherein n is an integer of from 2 to 249.

17. The method according to claim 1 , wherein n is an integer of from 2 to 99.

18. The method according to claim 1 , wherein n is an integer of from 2 to 49.

19. The method according to claim 1 , wherein n is an integer of from 9 to 49.

20. The method according to claim 1 , wherein n is an integer of from 14 to 39.

21. The method according to claim 1 , wherein n is an integer of from 19 to 24.