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Charles M. Nyachoti - One of the best experts on this subject based on the ideXlab platform.
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comparative efficacy of Xylanases on growth performance and digestibility in growing pigs fed wheat and wheat bran or corn and corn ddgs based diets supplemented with phytase
Animal Feed Science and Technology, 2015Co-Authors: S P Ndou, E Kiarie, A K Agyekum, L F Romero, Susan Lund Arent, R Lorentsen, Charles M. NyachotiAbstract:Two experiments were conducted to determine the effects of supplemental Xylanases on growth performance, coefficients of apparent ileal (CAID) and total tract (CATTD) digestibility in growing pigs fed wheat- or corn -based diets. Two basal diets were formulated based on either corn plus 40% corn distillers dried grains with solubles or wheat plus 25% wheat co-products and fed without or with five Xylanases from different microbial origins. The Xylanases were identified as A, B, C, D and E and fed at 75 mg of xylanase protein/kg of feed. All diets contained added phytase. In Experiment 1, the diets were offered for 42 d to 96 individually penned gilts (29.0 ± 0.2 kg) to give 8 pigs per diet. An interaction between diet type and xylanase was observed for ADG (P < 0.05) such that pigs fed wheat diets with Xylanases A and C and corn diets with Xylanases A and D had greater (P = 0.044) ADG than pigs fed xylanase-free diets or wheat diets with xylanase D or corn diets with Xylanases B and C. A main effect of xylanase was observed for G:F in which case xylanase A improved G:F by 10% (P = 0.010) compared to the control. In Experiment 2, TiO2 (3 g/kg) was added in all diets and pigs were allotted diets in a Youden Square design, to give 6 replicates per diet. Interaction (P < 0.05) between diet type and xylanase were observed on CAID of gross energy (GE), insoluble arabinose and xylose (iAX), total arabinose and xylose (tAX), insoluble NSP (iNSP), and total NSP (tNSP). In this context, pigs fed wheat-based diets with xylanase C and D and those fed corn-based diets with Xylanases B and E had greater (P < 0.05) CAID of GE compared to those fed xylanase-free diets. The CAID of tAX and tNSP in pigs fed wheat-based diets with xylanase C and corn-based diets with Xylanases B and E were higher (P < 0.001) than in pigs fed the other diets. There was no treatment effects on CATTD of GE, DM and crude protein, however, Xylanases independently improved (P = 0.040) CATTD of fat compared to the control. Different Xylanases responded differently in improving dietary components digestibility and growth performance depending on the diet type. However, the comparisons made in the present study are only valid for the test conditions as some of the Xylanases may have been dosed at levels below the biological optimum and others well above.
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comparative efficacy of Xylanases on growth performance and digestibility in growing pigs fed wheat and wheat bran or corn and corn ddgs based diets supplemented with phytase
Animal Feed Science and Technology, 2015Co-Authors: S P Ndou, E Kiarie, A K Agyekum, L F Romero, Susan Lund Arent, R Lorentsen, J M Heo, Charles M. NyachotiAbstract:Abstract Two experiments were conducted to determine the effects of supplemental Xylanases on growth performance, coefficients of apparent ileal (CAID) and total tract (CATTD) digestibility in growing pigs fed wheat- or corn -based diets. Two basal diets were formulated based on either corn plus 40% corn distillers dried grains with solubles or wheat plus 25% wheat co-products and fed without or with five Xylanases from different microbial origins. The Xylanases were identified as A, B, C, D and E and fed at 75 mg of xylanase protein/kg of feed. All diets contained added phytase. In Experiment 1, the diets were offered for 42 d to 96 individually penned gilts (29.0 ± 0.2 kg) to give 8 pigs per diet. An interaction between diet type and xylanase was observed for ADG (P
E Kiarie - One of the best experts on this subject based on the ideXlab platform.
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comparative efficacy of Xylanases on growth performance and digestibility in growing pigs fed wheat and wheat bran or corn and corn ddgs based diets supplemented with phytase
Animal Feed Science and Technology, 2015Co-Authors: S P Ndou, E Kiarie, A K Agyekum, L F Romero, Susan Lund Arent, R Lorentsen, Charles M. NyachotiAbstract:Two experiments were conducted to determine the effects of supplemental Xylanases on growth performance, coefficients of apparent ileal (CAID) and total tract (CATTD) digestibility in growing pigs fed wheat- or corn -based diets. Two basal diets were formulated based on either corn plus 40% corn distillers dried grains with solubles or wheat plus 25% wheat co-products and fed without or with five Xylanases from different microbial origins. The Xylanases were identified as A, B, C, D and E and fed at 75 mg of xylanase protein/kg of feed. All diets contained added phytase. In Experiment 1, the diets were offered for 42 d to 96 individually penned gilts (29.0 ± 0.2 kg) to give 8 pigs per diet. An interaction between diet type and xylanase was observed for ADG (P < 0.05) such that pigs fed wheat diets with Xylanases A and C and corn diets with Xylanases A and D had greater (P = 0.044) ADG than pigs fed xylanase-free diets or wheat diets with xylanase D or corn diets with Xylanases B and C. A main effect of xylanase was observed for G:F in which case xylanase A improved G:F by 10% (P = 0.010) compared to the control. In Experiment 2, TiO2 (3 g/kg) was added in all diets and pigs were allotted diets in a Youden Square design, to give 6 replicates per diet. Interaction (P < 0.05) between diet type and xylanase were observed on CAID of gross energy (GE), insoluble arabinose and xylose (iAX), total arabinose and xylose (tAX), insoluble NSP (iNSP), and total NSP (tNSP). In this context, pigs fed wheat-based diets with xylanase C and D and those fed corn-based diets with Xylanases B and E had greater (P < 0.05) CAID of GE compared to those fed xylanase-free diets. The CAID of tAX and tNSP in pigs fed wheat-based diets with xylanase C and corn-based diets with Xylanases B and E were higher (P < 0.001) than in pigs fed the other diets. There was no treatment effects on CATTD of GE, DM and crude protein, however, Xylanases independently improved (P = 0.040) CATTD of fat compared to the control. Different Xylanases responded differently in improving dietary components digestibility and growth performance depending on the diet type. However, the comparisons made in the present study are only valid for the test conditions as some of the Xylanases may have been dosed at levels below the biological optimum and others well above.
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comparative efficacy of Xylanases on growth performance and digestibility in growing pigs fed wheat and wheat bran or corn and corn ddgs based diets supplemented with phytase
Animal Feed Science and Technology, 2015Co-Authors: S P Ndou, E Kiarie, A K Agyekum, L F Romero, Susan Lund Arent, R Lorentsen, J M Heo, Charles M. NyachotiAbstract:Abstract Two experiments were conducted to determine the effects of supplemental Xylanases on growth performance, coefficients of apparent ileal (CAID) and total tract (CATTD) digestibility in growing pigs fed wheat- or corn -based diets. Two basal diets were formulated based on either corn plus 40% corn distillers dried grains with solubles or wheat plus 25% wheat co-products and fed without or with five Xylanases from different microbial origins. The Xylanases were identified as A, B, C, D and E and fed at 75 mg of xylanase protein/kg of feed. All diets contained added phytase. In Experiment 1, the diets were offered for 42 d to 96 individually penned gilts (29.0 ± 0.2 kg) to give 8 pigs per diet. An interaction between diet type and xylanase was observed for ADG (P
Nathalie Juge - One of the best experts on this subject based on the ideXlab platform.
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emergence of a subfamily of xylanase inhibitors within glycoside hydrolase family 18
FEBS Journal, 2005Co-Authors: Anne Durand, Ruth Flatman, Richard K. Hughes, Alain Roussel, Nathalie Juge, Bernard HenrissatAbstract:The xylanase inhibitor protein I (XIP-I), recently identified in wheat, inhibits Xylanases belonging to glycoside hydrolase families 10 (GH10) and 11 (GH11). Sequence and structural similarities indicate that XIP-I is related to chitinases of family GH18, despite its lack of enzymatic activity. Here we report the identification and biochemical characterization of a XIP-type inhibitor from rice. Despite its initial classification as a chitinase, the rice inhibitor does not exhibit chitinolytic activity but shows specificities towards fungal GH11 Xylanases similar to that of its wheat counterpart. This, together, with an analysis of approximately 150 plant members of glycosidase family GH18 provides compelling evidence that xylanase inhibitors are largely represented in this family, and that this novel function has recently emerged based on a common scaffold. The plurifunctionality of GH18 members has major implications for genomic annotations and predicted gene function. This study provides new information which will lead to a better understanding of the biological significance of a number of GH18 ‘inactivated’ chitinases.
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the dual nature of the wheat xylanase protein inhibitor xip i structural basis for the inhibition of family 10 and family 11 Xylanases
Journal of Biological Chemistry, 2004Co-Authors: Francoise Payan, Anne Durand, Philippe Leone, S Porciero, Caroline S M Furniss, T Tahir, Gary Williamson, Paloma Manzanares, Harry J Gilbert, Nathalie JugeAbstract:Abstract The xylanase inhibitor protein I (XIP-I) from wheat Triticum aestivum is the prototype of a novel class of cereal protein inhibitors that inhibit fungal Xylanases belonging to glycoside hydrolase families 10 (GH10) and 11 (GH11). The crystal structures of XIP-I in complex with Aspergillus nidulans (GH10) and Penicillium funiculosum (GH11) Xylanases have been solved at 1.7 and 2.5 A resolution, respectively. The inhibition strategy is novel because XIP-I possesses two independent enzyme-binding sites, allowing binding to two glycoside hydrolases that display a different fold. Inhibition of the GH11 xylanase is mediated by the insertion of an XIP-I Π-shaped loop (Lα4β5) into the enzyme active site, whereas residues in the helix α7 of XIP-I, pointing into the four central active site subsites, are mainly responsible for the reversible inactivation of GH10 Xylanases. The XIP-I strategy for inhibition of Xylanases involves substrate-mimetic contacts and interactions occluding the active site. The structural determinants of XIP-I specificity demonstrate that the inhibitor is able to interact with GH10 and GH11 Xylanases of both fungal and bacterial origin. The biological role of the xylanase inhibitors is discussed in light of the present structural data.
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Interactions defining the specificity between fungal Xylanases and the xylanase-inhibiting protein XIP-I from wheat.
The Biochemical journal, 2002Co-Authors: Ruth Flatman, Richard K. Hughes, Nathalie Juge, Paloma Manzanares, W Russell Mclauchlan, Caroline Furniss, Jean-guy Berrin, John E Ladbury, Ronan O'brien, Gary WilliamsonAbstract:We previously reported on the xylanase-inhibiting protein I (XIP-I) from wheat [McLauchlan, Garcia-Conesa, Williamson, Roza, Ravestein and Maat (1999), Biochem. J. 338, 441-446]. In the present study, we show that XIP-I inhibits family-10 and -11 fungal Xylanases. The K(i) values for fungal Xylanases ranged from 3.4 to 610 nM, but bacterial family-10 and -11 Xylanases were not inhibited. Unlike many glycosidase inhibitors, XIP-I was not a slow-binding inhibitor of the Aspergillus niger xylanase. Isothermal titration calorimetry of the XIP-I-A. niger xylanase complex showed the formation of a stoichiometric (1:1) complex with a heat capacity change of -1.38 kJ x mol(-1) x K(-1), leading to a predicted buried surface area of approx. 2200+/-500 A(2) at the complex interface. For this complex with A. niger xylanase (K(i)=320 nM at pH 5.5), titration curves indicated that an observable interaction occurred at pH 4-7, and this was consistent with the pH profile of inhibition of activity. In contrast, the stronger complex between A. nidulans xylanase and XIP-I (K(i)=9 nM) led to an observable interaction across the entire pH range tested (3-9). Using surface plasmon resonance, we show that the differences in the binding affinity of XIP-I for A. niger and A. nidulans xylanase are due to a 200-fold lower dissociation rate k(off) for the latter, with only a small difference in association rate k(on).
S P Ndou - One of the best experts on this subject based on the ideXlab platform.
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comparative efficacy of Xylanases on growth performance and digestibility in growing pigs fed wheat and wheat bran or corn and corn ddgs based diets supplemented with phytase
Animal Feed Science and Technology, 2015Co-Authors: S P Ndou, E Kiarie, A K Agyekum, L F Romero, Susan Lund Arent, R Lorentsen, Charles M. NyachotiAbstract:Two experiments were conducted to determine the effects of supplemental Xylanases on growth performance, coefficients of apparent ileal (CAID) and total tract (CATTD) digestibility in growing pigs fed wheat- or corn -based diets. Two basal diets were formulated based on either corn plus 40% corn distillers dried grains with solubles or wheat plus 25% wheat co-products and fed without or with five Xylanases from different microbial origins. The Xylanases were identified as A, B, C, D and E and fed at 75 mg of xylanase protein/kg of feed. All diets contained added phytase. In Experiment 1, the diets were offered for 42 d to 96 individually penned gilts (29.0 ± 0.2 kg) to give 8 pigs per diet. An interaction between diet type and xylanase was observed for ADG (P < 0.05) such that pigs fed wheat diets with Xylanases A and C and corn diets with Xylanases A and D had greater (P = 0.044) ADG than pigs fed xylanase-free diets or wheat diets with xylanase D or corn diets with Xylanases B and C. A main effect of xylanase was observed for G:F in which case xylanase A improved G:F by 10% (P = 0.010) compared to the control. In Experiment 2, TiO2 (3 g/kg) was added in all diets and pigs were allotted diets in a Youden Square design, to give 6 replicates per diet. Interaction (P < 0.05) between diet type and xylanase were observed on CAID of gross energy (GE), insoluble arabinose and xylose (iAX), total arabinose and xylose (tAX), insoluble NSP (iNSP), and total NSP (tNSP). In this context, pigs fed wheat-based diets with xylanase C and D and those fed corn-based diets with Xylanases B and E had greater (P < 0.05) CAID of GE compared to those fed xylanase-free diets. The CAID of tAX and tNSP in pigs fed wheat-based diets with xylanase C and corn-based diets with Xylanases B and E were higher (P < 0.001) than in pigs fed the other diets. There was no treatment effects on CATTD of GE, DM and crude protein, however, Xylanases independently improved (P = 0.040) CATTD of fat compared to the control. Different Xylanases responded differently in improving dietary components digestibility and growth performance depending on the diet type. However, the comparisons made in the present study are only valid for the test conditions as some of the Xylanases may have been dosed at levels below the biological optimum and others well above.
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comparative efficacy of Xylanases on growth performance and digestibility in growing pigs fed wheat and wheat bran or corn and corn ddgs based diets supplemented with phytase
Animal Feed Science and Technology, 2015Co-Authors: S P Ndou, E Kiarie, A K Agyekum, L F Romero, Susan Lund Arent, R Lorentsen, J M Heo, Charles M. NyachotiAbstract:Abstract Two experiments were conducted to determine the effects of supplemental Xylanases on growth performance, coefficients of apparent ileal (CAID) and total tract (CATTD) digestibility in growing pigs fed wheat- or corn -based diets. Two basal diets were formulated based on either corn plus 40% corn distillers dried grains with solubles or wheat plus 25% wheat co-products and fed without or with five Xylanases from different microbial origins. The Xylanases were identified as A, B, C, D and E and fed at 75 mg of xylanase protein/kg of feed. All diets contained added phytase. In Experiment 1, the diets were offered for 42 d to 96 individually penned gilts (29.0 ± 0.2 kg) to give 8 pigs per diet. An interaction between diet type and xylanase was observed for ADG (P
Georges Feller - One of the best experts on this subject based on the ideXlab platform.
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use of glycoside hydrolase family 8 Xylanases in baking
Journal of Cereal Science, 2006Co-Authors: Tony Collins, Anne Hoyoux, Agnes Dutron, Bernard Genot, Thierry Dauvrin, Jacques Georis, Charles Gerday, Filip Arnaut, Georges FellerAbstract:Xylanases have long been used in the baking industry for improving dough stability and flexibility and for increasing bread volume and crumb structure. Only Xylanases from glycoside hydrolase families 10 and 11 appear to have been tested in this application and only those from the latter family have as yet found application. Interestingly, enzymes with a putative xylanase activity are also found in glycoside hydrolase families 5, 7, 8 and 43, but apparently these have not, as yet, been tested in baking. Baking trials were used to determine the effectiveness of a psychrophilic and a mesophilic family 8 xylanolytic enzyme as well as a psychrophilic family 10 xylanase and a currently used family 11 commercial mesophilic xylanase. The potential of family 8 Xylanases as technological aids in baking was clearly demonstrated as both the psychrophilic enzyme from Pseudoalteromonas haloplanktis TAH3a and the mesophilic enzyme from Bacillus halodurans C-125 had a positive effect on loaf volume. In contrast, the psychrophilic family 10 enzyme from Cryptococcus adeliae TAE85 was found to be ineffective.
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Xylanases, xylanase families and extremophilic Xylanases
Fems Microbiology Reviews, 2005Co-Authors: Tony Collins, Charles Gerday, Georges FellerAbstract:Xylanases are hydrolytic enzymes which randomly cleave the β 1,4 backbone of the complex plant cell wall polysaccharide xylan. Diverse forms of these enzymes exist, displaying varying folds, mechanisms of action, substrate specificities, hydrolytic activities (yields, rates and products) and physicochemical characteristics. Research has mainly focused on only two of the xylanase containing glycoside hydrolase families, namely families 10 and 11, yet enzymes with xylanase activity belonging to families 5, 7, 8 and 43 have also been identified and studied, albeit to a lesser extent. Driven by industrial demands for enzymes that can operate under process conditions, a number of extremophilic Xylanases have been isolated, in particular those from thermophiles, alkaliphiles and acidiphiles, while little attention has been paid to cold-adapted Xylanases. Here, the diverse physicochemical and functional characteristics, as well as the folds and mechanisms of action of all six xylanase containing families will be discussed. The adaptation strategies of the extremophilic Xylanases isolated to date and the potential industrial applications of these enzymes will also be presented.
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a novel family 8 xylanase functional and physicochemical characterization
Journal of Biological Chemistry, 2002Co-Authors: Tony Collins, Georges Feller, Marie-alice Meuwis, Ingeborg Stals, Marc Claeyssens, Charles GerdayAbstract:Abstract Xylanases are generally classified into glycosyl hydrolase families 10 and 11 and are found to frequently have an inverse relationship between their pI and molecular mass values. However, we have isolated a psychrophilic xylanase that belongs to family 8 and which has both a high pI and high molecular mass. This novel xylanase, isolated from the Antarctic bacteriumPseudoalteromonas haloplanktis, is not homologous to family 10 or 11 enzymes but has 20–30% identity with family 8 members. NMR analysis shows that this enzyme hydrolyzes with inversion of anomeric configuration, in contrast to other known Xylanases which are retaining. No cellulase, chitosanase or lichenase activity was detected. It appears to be functionally similar to family 11 Xylanases. It hydrolyzes xylan to principally xylotriose and xylotetraose and is most active on long chain xylo-oligosaccharides. Kinetic studies indicate that it has a large substrate binding cleft, containing at least six xylose-binding subsites. Typical psychrophilic characteristics of a high catalytic activity at low temperatures and low thermal stability are observed. An evolutionary tree of family 8 enzymes revealed the presence of six distinct clusters. Indeed classification in family 8 would suggest an (α/α)6fold, distinct from that of other currently known Xylanases.
