Unraveling Synergism between Various GH Family Xylanases and Debranching Enzymes during Hetero-Xylan Degradation

Enzymes classified with the same Enzyme Commission (EC) that are allotted in different glycoside hydrolase (GH) families can display different mechanisms of action and substrate specificities. Therefore, the combination of different enzyme classes may not yield synergism during biomass hydrolysis, as the GH family allocation of the enzymes influences their behavior. As a result, it is important to understand which GH family combinations are compatible to gain knowledge on how to efficiently depolymerize biomass into fermentable sugars. We evaluated GH10 (Xyn10D and XT6) and GH11 (XynA and Xyn2A) β-xylanase performance alone and in combination with various GH family α-l-arabinofuranosidases (GH43 AXH-d and GH51 Abf51A) and α-d-glucuronidases (GH4 Agu4B and GH67 AguA) during xylan depolymerization. No synergistic enhancement in reducing sugar, xylose and glucuronic acid released from beechwood xylan was observed when xylanases were supplemented with either one of the glucuronidases, except between Xyn2A and AguA (1.1-fold reducing sugar increase). However, overall sugar release was significantly improved (≥1.1-fold reducing sugar increase) when xylanases were supplemented with either one of the arabinofuranosidases during wheat arabinoxylan degradation. Synergism appeared to result from the xylanases liberating xylo-oligomers, which are the preferred substrates of the terminal arabinofuranosyl-substituent debranching enzyme, Abf51A, allowing the exolytic β-xylosidase, SXA, to have access to the generated unbranched xylo-oligomers. Here, it was shown that arabinofuranosidases are key enzymes in the efficient saccharification of hetero-xylan into xylose. This study demonstrated that consideration of GH family affiliations of the carbohydrate-active enzymes (CAZymes) used to formulate synergistic enzyme cocktails is crucial for achieving efficient biomass saccharification.

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Genomic and transcriptomic analysis of the thermophilic lignocellulose-degrading fungus Thielavia terrestris LPH172

10.21203/rs.3.rs-96298/v1 ◽

2020 ◽

Author(s):

Monika Tõlgo ◽

Silvia Hüttner ◽

Nguyen Than Thuy ◽

Vu Nguyen Than ◽

Johan Larsbrink ◽

...

Keyword(s):

Gc Content ◽

Low Ph ◽

Biomass Degradation ◽

Carbohydrate Active Enzymes ◽

Thielavia Terrestris ◽

Biomass Saccharification ◽

Lignocellulosic Substrates ◽

Lytic Polysaccharide Monooxygenases ◽

Beechwood Xylan ◽

Polysaccharide Monooxygenases

Abstract Background: Biomass-degrading enzymes with improved activity and stability can ameliorate substrate saccharification and make biorefineries economically feasible. Filamentous fungi are a rich source of carbohydrate-active enzymes (CAZymes) for biomass degradation. The newly isolated LPH172 strain of the thermophilic Ascomycete Thielavia terrestris has been shown to possess high xylanase and cellulase activities and tolerate well low pH and high temperatures. Here, we aimed to illuminate the lignocellulose degrading machinery and novel carbohydrate-active enzymes in LPH172 in detail.Results: We sequenced and analysed the 36.6-Mb genome and transcriptome of LPH172 during growth on glucose, cellulose, rice straw, and beechwood xylan. In total, 411 CAZy domains were found among 10,128 predicted genes. Compared to other fungi, auxiliary activity (AA) enzymes were particularly enriched. GC content was higher in coding sequences than in the overall genome. A high GC3 content was hypothesised to contribute to thermophilicity. T. terrestris employed mainly lytic polysaccharide monooxygenases (LPMOs) and glycoside hydrolase (GH) family 7 glucanases to attack cellulosic substrates, and conventional hemicellulases (GH10 and GH11) to degrade xylan. The observed co-expression and co-upregulation of AA9 LPMOs, other AA CAZymes, and (hemi)cellulases points to a complex and nuanced degradation strategy. Growth on more complex and heterogeneous substrates resulted in a more varied but generally lower gene expression. Conclusions: Our analysis of the genome and transcriptome of T. terrestris LPH172 elucidates the enzyme arsenal the fungus uses to degrade lignocellulosic substrates. The study provides the basis for future characterisation of potential new enzymes for industrial biomass saccharification.

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Genomic and transcriptomic analysis of the thermophilic lignocellulose-degrading fungus Thielavia terrestris LPH172

Biotechnology for Biofuels ◽

10.1186/s13068-021-01975-1 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Monika Tõlgo ◽

Silvia Hüttner ◽

Peter Rugbjerg ◽

Nguyen Thanh Thuy ◽

Vu Nguyen Thanh ◽

...

Keyword(s):

Gc Content ◽

Carbohydrate Active Enzymes ◽

Lytic Polysaccharide Monooxygenase ◽

Thielavia Terrestris ◽

Biomass Saccharification ◽

Beechwood Xylan ◽

Genes Encoding ◽

Encoding Genes ◽

Polysaccharide Monooxygenase

Abstract Background Biomass-degrading enzymes with improved activity and stability can increase substrate saccharification and make biorefineries economically feasible. Filamentous fungi are a rich source of carbohydrate-active enzymes (CAZymes) for biomass degradation. The newly isolated LPH172 strain of the thermophilic Ascomycete Thielavia terrestris has been shown to possess high xylanase and cellulase activities and tolerate low pH and high temperatures. Here, we aimed to illuminate the lignocellulose-degrading machinery and novel carbohydrate-active enzymes in LPH172 in detail. Results We sequenced and analyzed the 36.6-Mb genome and transcriptome of LPH172 during growth on glucose, cellulose, rice straw, and beechwood xylan. 10,128 predicted genes were found in total, which included 411 CAZy domains. Compared to other fungi, auxiliary activity (AA) domains were particularly enriched. A higher GC content was found in coding sequences compared to the overall genome, as well as a high GC3 content, which is hypothesized to contribute to thermophilicity. Primarily auxiliary activity (AA) family 9 lytic polysaccharide monooxygenase (LPMO) and glycoside hydrolase (GH) family 7 glucanase encoding genes were upregulated when LPH172 was cultivated on cellulosic substrates. Conventional hemicellulose encoding genes (GH10, GH11 and various CEs), as well as AA9 LPMOs, were upregulated when LPH172 was cultivated on xylan. The observed co-expression and co-upregulation of genes encoding AA9 LPMOs, other AA CAZymes, and (hemi)cellulases point to a complex and nuanced degradation strategy. Conclusions Our analysis of the genome and transcriptome of T. terrestris LPH172 elucidates the enzyme arsenal that the fungus uses to degrade lignocellulosic substrates. The study provides the basis for future characterization of potential new enzymes for industrial biomass saccharification.

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Investigation of polyphenol synergism for reducing sugar release from white bread

Proceedings of The Nutrition Society ◽

10.1017/s0029665115000828 ◽

2015 ◽

Vol 74 (OCE1) ◽

Cited By ~ 1

Author(s):

S. Coe ◽

L. Ryan

Keyword(s):

Reducing Sugar ◽

White Bread ◽

Sugar Release

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Complete Genome Sequence of the Cellulolytic Thermophile Caldicellulosiruptor obsidiansis OB47T

Journal of Bacteriology ◽

10.1128/jb.00950-10 ◽

2010 ◽

Vol 192 (22) ◽

pp. 6099-6100 ◽

Cited By ~ 36

Author(s):

James G. Elkins ◽

Adriane Lochner ◽

Scott D. Hamilton-Brehm ◽

Karen Walston Davenport ◽

Mircea Podar ◽

...

Keyword(s):

Lignocellulosic Biomass ◽

High Temperatures ◽

Genome Sequence ◽

Complete Genome Sequence ◽

Complete Genome ◽

Anaerobic Bacterium ◽

Carbohydrate Active Enzymes ◽

Biomass Hydrolysis ◽

Insight Into

ABSTRACT Caldicellulosiruptor obsidiansis OB47T (ATCC BAA-2073, JCM 16842) is an extremely thermophilic, anaerobic bacterium capable of hydrolyzing plant-derived polymers through the expression of multidomain/multifunctional hydrolases. The complete genome sequence reveals a diverse set of carbohydrate-active enzymes and provides further insight into lignocellulosic biomass hydrolysis at high temperatures.

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Whole Genome Sequence and CAZyme distribution of the cellulase hyper producing filamentous fungus Penicillium janthinellum NCIM 1366

10.1101/2021.06.17.448855 ◽

2021 ◽

Author(s):

Meera K Christopher ◽

AthiraRaj Sreeja-Raju ◽

Prajeesh K Kooloth-Valappil ◽

Amith Abraham ◽

Digambar Vitthal Gokhale ◽

...

Keyword(s):

De Novo ◽

Cellulase Production ◽

Whole Genome Sequence ◽

Lignocellulose Degradation ◽

Carbohydrate Active Enzymes ◽

Biomass Hydrolysis ◽

Penicillium Janthinellum ◽

Trichoderma Reesei Rut C30 ◽

Hydrolysis Of ◽

Rut C30

Penicillium janthinellum NCIM 1366, capable of secreting cellulases that are highly efficient in the hydrolysis of lignocellulosic biomass, was sequenced to understand its cellulolytic machinery. De novo sequencing and assembly revealed a 37.6 Mb genome encoding 11,848 putative proteins, 93% of which had significant BLAST-P hits. The majority of the top hits (those with over 60% UniProt identity) belonged to P. brasilianum. Carbohydrate active enzymes (CAZymes) and other enzymes involved in lignocellulose degradation were also predicted from this strain and compared with those of the industrial workhorse of cellulase production- Trichoderma reesei RUT-C30. The comparison showed that the fungus encodes a far higher number of CAZYmes (422) as compared to T. reesei RUT-C30 (244), which gives a plausible explanation for its overall effectiveness in biomass hydrolysis. An analysis of the secreted CAZymes and annotated ligninases identified 216 predicted proteins which may be directly involved in the breakdown of lignocellulose

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Freeze-Thaw and Sulfuric Acid Pretreatment of Wheat Straw for Fermentable Sugar Release

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.724-725.257 ◽

2013 ◽

Vol 724-725 ◽

pp. 257-260 ◽

Cited By ~ 2

Author(s):

Xin Ming Wang ◽

Lian Jie Wang ◽

Meng Yu ◽

Hui Chen

Keyword(s):

Sulfuric Acid ◽

Wheat Straw ◽

Reducing Sugar ◽

Acid Pretreatment ◽

Sugar Release ◽

Freeze Thaw ◽

Treatment Conditions ◽

Sulfuric Acid Pretreatment ◽

Hydrolysis Of Cellulose ◽

Hydrolysis Of

Hydrolysis of cellulose and hemicelluloses of lignocellulosic materials to obtain reducing sugar can be used to produce ethanol by microbial fermentation. Effective pretreatment is necessary for optimal hydrolysis. This study investigated the positive effect of freeze-thaw treatment on low temperature sulfuric acid pretreatment for convert wheat straw to reducing sugar. Freeze-thaw treatment conditions were optimized: at -20°C for 12h, and at room temperature (25°C) for 1h, followed. After twice repeating of freeze-thaw treatment and pretreatment with 2wt% sulfuric acid for 16h at 80°C and enzymatic digestibility with 20U/g of cellulase loading, 67% cellulose and hemicelluloses were converted to glucose and xylose. The yield of furfural was decreased by 65% during sulfuric acid pretreatment. The time of acid hydrolysis was shortened by 20%.

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Studies of rice debranching enzyme. Part VI. Conversion of active and inactive debranching enzymes in rice seeds.

Agricultural and Biological Chemistry ◽

10.1271/bbb1961.45.747 ◽

1981 ◽

Vol 45 (3) ◽

pp. 747-750 ◽

Cited By ~ 8

Author(s):

Jiro YAMADA

Keyword(s):

Debranching Enzyme ◽

Debranching Enzymes ◽

Rice Seeds

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Changes in the Saccharoid Fraction in Rats with Alloxan-Induced Diabetes or Injected with Epinephrine

Clinical Chemistry ◽

10.1093/clinchem/17.9.915 ◽

1971 ◽

Vol 17 (9) ◽

pp. 915-920 ◽

Cited By ~ 7

Author(s):

M Jafar Alam ◽

M Ataur Rahman

Keyword(s):

Ascorbic Acid ◽

Uric Acid ◽

Blood Glucose ◽

Glucose Concentration ◽

Glucuronic Acid ◽

Blood Glucose Concentration ◽

Diabetic Rats ◽

Reducing Sugar ◽

Sugar Phosphates ◽

Reducing Substances

Abstract "Saccharoid fraction," defined as the nonglucose reducing substances in blood, increases both in hyperglycemia (blood glucose concentration exceeding 280 mg/dl) and hypoglycemia (blood sugar less than 65 mg/dl) in rats. This increase is not completely accounted for by glutathione, glucuronic acid, ascorbic acid, uric acid, and creatinine. Some of the constituents of saccharoid fraction seem to be insulin-sensitive. Alloxan not only produces diabetes in rats but also increases blood glucuronic acid, ascorbic acid, and uric acid. Estimated constituents of saccharoid fraction account for only 45% to 75% of the saccharoid fraction. The unaccounted-for saccharoid fraction shows changes similar to those in the accounted-for saccharoid fraction, in the diabetic rats, as was also the case after treatment with insulin of normal or diabetic animals. The fraction not accounted for by the estimated constituents may represent the reducing sugar phosphates present in the blood.

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