Compositions for enhancing hydroysis of cellulosic material by cellulolytic enzyme compositions
The present invention relates to compositions comprising a GH61 polypeptide having cellulolytic enhancing activity and an organic compound comprising a carboxylic acid moiety, a lactone moiety, a phenolic moiety, a flavonoid moiety, or a combination thereof, wherein the combination of the GH61 polypeptide having cellulolytic enhancing activity and the organic compound enhances hydrolysis of a cellulosic material by a cellulolytic enzyme compared to the GH61 polypeptide alone or the organic compound alone. The present invention also relates to methods of using the compositions.
1. An aqueous composition comprising: (a) a GH61 polypeptide having cellulolytic enhancing activity and (b) an organic compound comprising a carboxylic acid moiety, a lactone moiety, a phenolic moiety, a flavonoid moiety, or a combination thereof, wherein the combination of the GH61 polypeptide having cellulolytic enhancing activity and the organic compound enhances hydrolysis of a cellulosic material by a cellulolytic enzyme compared to the GH61 polypeptide alone or the organic compound alone, and wherein the proton dissociated form of the organic compound is neutral or anionic with respect to the proton dissociated moiety.
2. The composition of claim 1 , wherein the organic compound comprises a pKa that is less than or about equal to the pH of the composition.
3. The composition of claim 1 , wherein the pH of the composition is greater than or equal to about 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, or 8.0.
4. The composition of claim 1 , wherein the organic compound comprises a pKa less than or equal to about 8.0, 7.5, 7.0, 6.5, 6.0, 5.5, 5.0, 4.5, 3.5, 3.0, or 2.5.
5. The composition of claim 1 , wherein greater than or about 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 5%, 2.5%, or 1% of the organic compound is in proton dissociated form.
6. The composition of claim 1 , wherein the organic compound is selected from the group consisting of: methyl-4-hydroxybenzoate; 3,5-dihydroxybenzoic acid; 4-hydroxybenzoic acid; glutamic acid; tartaric acid; 4-hydroxy-3-methoxycinnamic acid; methyl-3,4,5-trihydroxybenzoate; 3,4-dihydroxybenzoic acid; ascorbic acid; 4-methyl hexanoic acid; 2-methyl hexanoic acid; pyrocatechol; pyrogallol; dehydroascorbate; cysteine; gallic acid; fumaric acid; trans-aconitic acid; methylmalonic acid; oxalic acid; sorbic acid; maleic acid; caproic acid; 4-hydroxy-3-methoxybenzoic acid; 2,6-dimethoxyphenol; abietic acid; 3,5-di-tert-butyl-4-hydroxybenzoic acid; 2-aminophenol; butyric acid; epicatechin; morin; naringenin; quercetin; and a salt or solvate thereof.
7. The composition of claim 1 , which further comprises (c) one or more enzymes selected from the group consisting of a cellulase, a hemicellulase, an esterase, an expansin, a laccase, a ligninolytic enzyme, a pectinase, a peroxidase, a protease, and a swollenin.
8. The composition of claim 1 , wherein the combination of the GH61 polypeptide having cellulolytic enhancing activity and the organic compound enhances hydrolysis of a cellulosic material by a cellulolytic enzyme according to the following formula with a ratio greater than 1:
GH
61
effect
=
%
conversion
(
+
GH
61
+
organic
compound
)
%
conversion
(
no
GH
61
+
organic
compound
)
.
9. The composition of claim 1 , wherein the effective amount of the organic compound to the cellulosic material as a molar ratio to glucosyl units of cellulose is about 10 −6 to about 10.
10. The composition of claim 1 , wherein the pH of the composition is greater than or about equal to about 5.0.
11. The composition of claim 1 , wherein the organic compound comprises a pKa less than or about equal to about 5.0.
12. The composition of claim 1 , wherein the organic compound comprises a carboxylic acid moiety.
13. The composition of claim 1 , wherein the organic compound comprises a lactone moiety.
14. The composition of claim 1 , wherein the organic compound comprises a phenolic moiety.
15. The composition of claim 1 , wherein the organic compound comprises a flavonoid moiety.
16. The composition of claim 1 which further comprises (c) one or more enzymes selected from the group consisting of a cellulase, a hemicellulase, an esterase, an expansin, a laccase, a ligninolytic enzyme, a pectinase, a peroxidase, a protease, and a swollenin.
17. The composition of claim 16 , wherein the cellulase is one or more enzymes selected from the group consisting of an endoglucanase, a cellobiohydrolase, and a beta-glucosidase.
18. The composition of claim 16 , wherein the hemicellulase is one or more enzymes selected from the group consisting of an acetylmannan esterase, an acetylxylan esterase, an arabinanase, an arabinofuranosidase, a coumaric acid esterase, a feruloyl esterase, a galactosidase, a glucuronidase, a glucuronoyl esterase, a mannanase, a mannosidase, a xylanase, and a xylosidase.
19. The composition of claim 1 , wherein the effective amount of the organic compound to the cellulosic material as a molar ratio to glucosyl units of cellulose is about 10 −5 to about 1.
20. The composition of claim 1 , wherein an effective amount of the organic compound to the cellulosic material as a molar ratio to glucosyl units of cellulose is about 10 −4 to about 10 −1 .
21. The composition of claim 1 , wherein an effective amount of the organic compound to the cellulosic material as a molar ratio to glucosyl units of cellulose is about 10 −3 to about 10 −2 .