Prices exclude VAT
Available for shipping
|> 2 years under recommended storage conditions
|Arabinose: Xylose = 40: 60
|Main Chain Glycosidic Linkage:
|Substrate For (Enzyme):
High purity Arabinoxylan (Rye Flour) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.
See our full range of carbohydrate products.
Induction and Characterisation of Lignocellulolytic Activities from Novel Deep-Sea Fungal Secretomes.
Dowd, B. & Tuohy, M. G. (2023). Fermentation, 9(9), 780.
Fungi are increasingly recognised as being able to inhabit extreme environments. The deep sea is considered an extreme environment because of its low temperatures, high hydrostatic and lithostatic pressures, 3.5% salinity, and low oxygen, nutrient and light availability. Fungi inhabiting the deep sea may have evolved to produce proteins that allow them to survive these conditions. Investigation and characterisation of fungal lignocellulolytic enzymes from extreme environments like the deep sea is needed, as they may have unusual adaptations that would be useful in industry. This work, therefore, aimed to profile in detail the lignocellulolytic capabilities of fungi isolated from deep-sea sediments in the Atlantic Ocean, and a comparative lignocellulolytic terrestrial isolate. The isolates were strains of Emericellopsis maritima, Penicillium chrysogenum, P. antarcticum and Talaromyces stollii. Lignocellulolytic enzyme induction was achieved using liquid-state fermentation (LSF) with wheat bran as the main carbon source, while enzyme characteristics were evaluated using biochemical assays and gel-based proteomics. This study revealed that the isolates were halotolerant, produced xylanase over wide pH and temperature ranges, and produced a variety of glycoside hydrolase and feruloyl esterase activities. The T. stollii secretome demonstrated remarkable levels of exo-glycoside hydrolase activity, with xylanase activity optimum between pH 1.5–6.0 and temperatures between 1–60 °C, making this isolate an ideal candidate for biotechnological applications. This study is the first to quantitatively characterise xylanase activities and exo-glycoside hydrolase activities secreted by E. maritima, P. antarcticum and a marine T. stollii strain. This study is also the first to quantitatively characterise xylanase activities by a marine strain of P. chrysogenum during LSF.Hide Abstract
Arabinoxylan source and xylanase specificity influence the production of oligosaccharides with prebiotic potential.
Rudjito, R. C., Jiménez-Quero, A., Muñoz, M. D. C. C., Kuil, T., Olsson, L., Stringer, M. A., Krogh, K. B. R. M., Eklof, J. & Vilaplana, F. (2023). Carbohydrate Polymers, 320, 121233.
Cereal arabinoxylans (AXs) are complex polysaccharides in terms of their pattern of arabinose and ferulic acid substitutions, which influence their properties in structural and nutritional applications. We have evaluated the influence of the molecular structure of three AXs from wheat and rye with distinct substitutions on the activity of β-xylanases from different glycosyl hydrolase families (GH 5_34, 8, 10 and 11). The arabinose and ferulic acid substitutions influence the accessibility of the xylanases, resulting in specific profiles of arabinoxylan-oligosaccharides (AXOS). The GH10 xylanase from Aspergillus aculeatus (AcXyn10A) and GH11 from Thermomyces lanuginosus (TlXyn11) showed the highest activity, producing larger amounts of small oligosaccharides in shorter time. The GH8 xylanase from Bacillus sp. (BXyn8) produced linear xylooligosaccharides and was most restricted by arabinose substitution, whereas GH5_34 from Gonapodya prolifera (GpXyn5_34) required arabinose substitution and produced longer (A)XOS substituted on the reducing end. The complementary substrate specificity of BXyn8 and GpXyn5_34 revealed how arabinoses were distributed along the xylan backbones. This study demonstrates that AX source and xylanase specificity influence the production of oligosaccharides with specific structures, which in turn impacts the growth of specific bacteria (Bacteroides ovatus and Bifidobacterium adolescentis) and the production of beneficial metabolites (short-chain fatty acids).Hide Abstract
Novel thermostable GH5_34 arabinoxylanase with an atypical CBM6, displays activity on oat fibre xylan for prebiotic production.
Norlander, S., Jasilionis, A., Ara, Z. G. K., Grey, C., Adlercreutz, P. & Karlsson, E. N. (2022). Glycobiology, In Press.
Carbohydrate active enzymes are valuable tools in cereal processing to valorise underutilized side streams. By solubilizing hemicellulose and modifying the fibre structure, novel food products with increased nutritional value can be created. In this study, a novel GH5_34 subfamily arabinoxylanase from Herbinix hemicellulosilytica, HhXyn5A, was identified, produced and extensively characterized, for the intended exploitation in cereal processing to solubilize potential prebiotic fibres; arabinoxylo-oligosaccharides (AXOS). The purified two-domain HhXyn5A (catalytic domain and CBM6) demonstrated high storage stability, showed a melting temperature Tm of 61 °C and optimum reaction conditions were determined to 55°C and pH 6.5 on wheat arabinoxylan (WAX). HhXyn5A demonstrated activity on various commercial cereal arabinoxylans and produced prebiotic AXOS, while the sole catalytic domain of HhXyn5A did not demonstrate detectable activity. HhXyn5A demonstrated no side activity on oat β-glucan. In contrast to the commercially available homologue CtXyn5A, HhXyn5A gave a more specific HPAEC–PAD oligosaccharide product profile when using WAX and alkali extracted oat bran fibres as substrate. Results from multiple sequence alignment of GH5_34 enzymes, homology modelling of HhXyn5A and docking simulations with ligands XXXA3, XXXA3XX, and X5, concluded that the active site of HhXyl5A catalytic domain is highly conserved and can accommodate both shorter and longer AXOS ligands. However, significant structural dissimilarities between HhXyn5A and CtXyn5A in the binding cleft of CBM6, due to lack of important ligand interacting residues, is suggested to cause the observed differences in substrate specificity and product formation.Hide Abstract
Duplication of horizontally acquired GH5_2 enzymes played a central role in the evolution of longhorned beetles.
Shin, N. R., Doucet, D. & Pauchet, Y. (2022). Molecular Biology and Evolution, 39(6), msac128.
The rise of functional diversity through gene duplication contributed to the adaption of organisms to various environments. Here we investigate the evolution of putative cellulases of the subfamily 2 of glycoside hydrolase family 5 (GH5_2) in the Cerambycidae (longhorned beetles), a megadiverse assemblage of mostly xylophagous beetles. Cerambycidae originally acquired GH5_2 from a bacterial donor through horizontal gene transfer (HGT), and extant species harbor multiple copies that arose from gene duplication. We ask how these digestive enzymes contributed to the ability of these beetles to feed on wood. We analyzed 113 GH5_2, including the functional characterization of 52 of them, derived from 25 species covering most subfamilies of Cerambycidae. Ancestral gene duplications led to five well-defined groups with distinct substrate specificity, allowing these beetles to break down, in addition to cellulose, polysaccharides that are abundant in plant cell walls (PCWs), namely, xyloglucan, xylan, and mannans. Resurrecting the ancestral enzyme originally acquired by HGT, we show it was a cellulase that was able to break down glucomannan and xylan. Finally, recent gene duplications further expanded the catalytic repertoire of cerambycid GH5_2, giving rise to enzymes that favor transglycosylation over hydrolysis. We suggest that HGT and gene duplication, which shaped the evolution of GH5_2, played a central role in the ability of cerambycid beetles to use a PCW-rich diet and may have contributed to their successful radiation.Hide Abstract
Partial acid-hydrolysis of TEMPO-oxidized arabinoxylans generates arabinoxylan-structure resembling oligosaccharides.
Pandeirada, C. O., Speranza, S., Bakx, E., Westphal, Y., Janssen, H. G. & Schols, H. A. (2021). Carbohydrate Polymers, 275, 118795.
Arabinoxylans (AXs) display biological activities that depend on their chemical structures. To structurally characterize and distinguish AXs using a non-enzymatic approach, various TEMPO-oxidized AXs were partially acid-hydrolysed to obtain diagnostic oligosaccharides (OS). Arabinurono-xylo-oligomer alditols (AUXOS-A) with degree of polymerization 2-5, comprising one and two arabinuronic acid (AraA) substituents were identified in the UHPLC-PGC-MS profiles of three TEMPO-oxidized AXs, namely wheat (ox-WAX), partially-debranched WAX (ox-pD-WAX), and rye (ox-RAX). Characterization of these AUXOS-A highlighted that single-substitution of the Xyl unit preferably occurs at position O-3 for these samples, and that ox-WAX has both more single substituted and more double-substituted xylose residues in its backbone than the other AXs. Characteristic UHPLC-PGC-MS OS profiles, differing in OS abundance and composition, were obtained for each AX. Thus, partial acid-hydrolysis of TEMPO-oxidized AXs with analysis of the released OS by UHPLC-PGC-MS is a promising novel non-enzymatic approach to distinguish AXs and obtain insights into their structures.Hide Abstract
Impact of condensed tannin interactions with grain proteins and non-starch polysaccharides on batter system properties.
Girard, A. L. & Awika, J. M. (2021). Food Chemistry, 359, 129969.
Proanthocyanidins (PA) cross-link wheat gluten proteins and dramatically enhance batter viscosity; PA could similarly affect related grains. This study aimed to determine PA effect on viscosity and pasting properties of barley, rye, and oat flours, and the relative contributions of PA interactions with proteins and non-starch polysaccharides (NSP). PA significantly increased batter viscosity, stability, and RVA peak viscosity in rye and barley flours (2.8× and 1.2×, respectively). Interestingly, viscosity peaked distinctively ~75°C in PA-treated rye and barley flours, and their isolated protein-starch systems, indicating prolamins unravelled and complexed with PA during heating. Oat was largely unaffected by PA, likely because of its protein composition. Furthermore, water-soluble rye NSP and arabinoxylans, but not barley β-glucans, significantly increased starch pasting viscosity with PA; oxidative gelation was not a factor. Thus, rye flour viscosity dramatically increased through interactive effects of PA on rye proteins and NSP, which could expand its food applications.Hide Abstract
Highly Efficient Degradation of Xylan into Xylose by a Single Enzyme.
Basit, A., Miao, T., Liu, J., Wen, J., Song, L., Zheng, F., Lou, H. & Jiang, W. (2019). ACS Sustainable Chemistry & Engineering, 7(13), 11360-11368.
Here, we report highly efficient degradation of xylan into xylose by a single multifunctional xylanolytic enzyme from the filamentous fungus Thermothelomyces thermophila (termed Ttxy43). Ttxy43 shows three different enzyme activities toward carbohydrates, β-xylosidase (80.8 U/mg), endoxylanase (105.42 U/mg), and α-l-arabinofuranosidase enzyme activities (15.81 U/mg). Analysis of the catalytic mode of action of Ttxy43 for birchwood-xylan (BWX) reveals that endoxylanase initially degrades xylan to unbranched xylooligosaccharides (XOSs) (xylobiose, xylotriose, xylotetraose) as intermediates, which are then quickly hydrolyzed into single xylose by β-xylosidase. Site-directed mutagenesis studies indicate that Ttxy43 residues Asp134 and Glu228 are essential catalytic sites, while Glu176, Asp38, and Asp85 play an accessory role. More importantly, Ttxy43 displays higher degradation efficiency in comparison with a commercial β-xylosidase and endoxylanase “cocktail”. These findings elucidate an efficient integrated degradation mechanism of xylan under industrial reaction conditions, which provides a novel strategy to design techniques for biomass energy production.Hide Abstract
Functional characterization and comparative analysis of two heterologous endoglucanases from diverging subfamilies of glycosyl hydrolase family 45.
Berto, G. L., Velasco, J., Ribeiro, C. T. C., Zanphorlin, L. M., Domingues, M. N., Murakami, M. T., Polikarpoy, I., Oliveira, L. C., Ferraz, A. & Segato, F. (2019). Enzyme and Microbial Technology, 120, 23-35.
Lignocellulosic materials are abundant, renewable and are emerging as valuable substrates for many industrial applications such as the production of second-generation biofuels, green chemicals and pharmaceuticals. However, the recalcitrance and the complexity of cell wall polysaccharides require multiple enzymes for their complete conversion to oligo- and monosaccharides. The endoglucanases from GH45 family are a small and relatively poorly studied group of enzymes with potential industrial application. The present study reports cloning, heterologous expression and functional characterization of two GH45 endoglucanases from mesophilic fungi Gloeophyllum trabeum (GtGH45) and thermophilic fungi Myceliophthora thermophila (MtGH45), which belong to subfamilies GH45C and GH45A, respectively. Both enzymes have optimal pH 5.0 and melting temperatures (Tm) of 66.0°C and 80.9°C, respectively, as estimated from circular dichroism experiments. The recombinant proteins also exhibited different mode of action when incubated with oligosaccharides ranging from cellotriose to cellohexaose, generating mainly cellobiose and cellotriose (MtGH45) or glucose and cellobiose (GtGH45). The MtGH45 did not show activity against oligosaccharides smaller than cellopentaose while the enzyme GtGH45 was able to depolymerize cellotriose, however with lower efficiency when compared to larger oligosaccharides. Furthermore, both GHs45 were stable up to 70°C for 24 h and useful to enhance initial glucan hydrolysis rates during saccharification of sugarcane pith by a mixture of cellulolytic enzymes. Recombinant GHs45 from diverging subfamilies stand out for differences in substrate specificity appearing as new tools for preparation of enzyme cocktails used in cellulose hydrolysis.Hide Abstract
Ruprecht, C., Dallabernardina, P., Smith, P. J., Urbanowicz, B. R. & Pfrengle, F. (2018). ChemBioChem, In Press.
The plant cell wall is a cellular exoskeleton consisting predominantly of a complex polysaccharide network that defines the shape of cells. During growth, this network can be loosened through the action of Xyloglucan Endo-Transglycosylases (XETs), glycoside hydrolases that 'cut and paste' xyloglucan polysaccharides through a transglycosylation process. We have analyzed cohorts of XETs in different plant species to evaluate xyloglucan acceptor substrate specificities using a set of synthetic oligosaccharides obtained by automated glycan assembly. The ability of XETs to incorporate the oligosaccharides into polysaccharides printed as microarrays and into stem sections of Arabidopsis thaliana, beans, and peas was assessed. We found that single xylose substitutions are sufficient for transfer, and xylosylation of the terminal glucose residue is not required by XETs, independently of plant species. To obtain some information on the potential xylosylation pattern of the natural acceptor of XETs, i.e. the non-reducing end of xyloglucan, we further tested the activity of xyloglucan xylosyl transferase (XXT) 2 on the synthetic xyloglucan oligosaccharides. This data sheds light on inconsistencies between previous studies towards determining the acceptor substrate specificities of XETs and have important implications for further understanding plant cell wall polysaccharide synthesis and remodeling.Hide Abstract