xylohexaose | 49694-21-5

• 物质功能分类: 分析化学 - 对照品
• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: xylohexaose
• 英文别名: xylohexose；Xylohexaose；(2R,3R,4R)-4-(((2S,3R,4R,5R)-5-(((2S,3R,4R,5R)-5-(((2S,3R,4R,5R)-5-(((2S,3R,4R,5R)-3,4-Dihydroxy-5-(((2S,3R,4S,5R)-3,4,5-trihydroxytetrahydro-2H-pyran-2-yl)oxy)tetrahydro-2H-pyran-2-yl)oxy)-3,4-dihydroxytetrahydro-2H-pyran-2-yl)oxy)-3,4-dihydroxytetrahydro-2H-pyran-2-yl)oxy)-3,4-dihydroxytetrahydro-2H-pyran-2-yl)oxy)-2,3,5-trihydroxypentanal；(2R,3R,4R)-4-[(2S,3R,4R,5R)-5-[(2S,3R,4R,5R)-5-[(2S,3R,4R,5R)-5-[(2S,3R,4R,5R)-3,4-dihydroxy-5-[(2S,3R,4S,5R)-3,4,5-trihydroxyoxan-2-yl]oxyoxan-2-yl]oxy-3,4-dihydroxyoxan-2-yl]oxy-3,4-dihydroxyoxan-2-yl]oxy-3,4-dihydroxyoxan-2-yl]oxy-2,3,5-trihydroxypentanal
• CAS: 49694-21-5
• 化学式: C₃₀H₅₀O₂₅
• 分子量: 810.712
• InChiKey: MMDRQFODAWORNG-QBYSOWFWSA-N

物化性质

• 熔点：
  236-237°C
• 比旋光度：
  -70 º (c=1% in H2O)
• 沸点：
  1142.7±65.0 °C(Predicted)
• 密度：
  1.77±0.1 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  -10.5
• 重原子数：
  55
• 可旋转键数：
  14
• 环数：
  5.0
• sp3杂化的碳原子比例：
  0.97
• 拓扑面积：
  393
• 氢给体数：
  14
• 氢受体数：
  25

制备方法与用途

生物活性方面，Xylohexaose 是一种由六个木糖残基构成的低聚木糖，并可作为木聚糖水解性能测定的底物。

反应信息

• 作为反应物：
  描述：

  xylohexaose 在 polyethylenimine-coated Selenomonas ruminantium β-xylosidase immobilized on glyoxyl agarose 、 水 作用下， 以 aq. acetate buffer 为溶剂， 反应 4.0h， 生成 木二糖
  参考文献：
  名称：

  β-xylosidase from Selenomonas ruminantium: Immobilization, stabilization, and application for xylooligosaccharide hydrolysis

  摘要：

  The tetrameric -xylosidase from Selenomonas ruminantium is very stable in alkaline pH allowing it to easily immobilize by multipoint covalent attachments on highly activated glyoxyl agarose gels. Initial immobilization resulted only in slight stabilization in relation to the free enzyme, since involvement of all subunits was not achieved. Coating the catalyst with aldehyde-dextran or polyethylenimine, fully stabilized the quaternary structure of the enzyme rendering much more stabilization to the biocatalyst. The catalyst coated with polyethylenimine of molecular weight 1300 is the most stable one exhibiting an interesting half-life of more than 10 days at pH 5.0 and 50 degrees C, being, therefore, 240-fold more stable than free enzyme. Optimum activity was observed in the pH range 4.0-6.0 and at 55 degrees C. The catalyst retained its side activity against p-nitrophenyl -l-arabinofuranoside and it was inhibited by xylose and glucose. Kinetic parameters with p-nitrophenyl -d-xylopyranoside as substrate were V-max 0.20mol.min(-1)mgprot.(-1), K-m 0.45mM, K-cat 0.82s(-1), and K-cat/K-m 1.82s(-1)mM(-1). Xylose release was observed from the hydrolysis of xylooligosaccharides with a decrease in the rate of xylose release by increasing substrate chain-length. Due to the high thermostability and the complete stability after five reuse cycles, the applicability of this biocatalyst in biotechnological processes, such as for the degradation of lignocellulosic biomass, is highly increased.

  DOI：

  10.1080/10242422.2016.1247817
• 作为产物：
  描述：

  alkaline earth salt of/the/ methylsulfuric acid 在 水 作用下， 生成 xylohexaose
  参考文献：
  名称：

  OLIGOSACCHARIDES OF XYLOSE FROM WHEAT STRAW HEMICELLULOSE

  摘要：

  一系列寡糖在120℃的蒸汽压力锅中，使用蒸馏水从小麦秸秆半纤维素中制备而成。其中二糖到七糖都属于(1→4)-β-D-木聚糖系列。八糖则被证明是双分支的。基于这些结果，讨论了小麦秸秆半纤维素的某些结构方面。

  DOI：

  10.1139/v55-124

文献信息

• Characterization of a recombinant multifunctional glycoside hydrolase family 3 β-xylosidase/α-l-arabinofuranosidase/β-glucosidase from Cellulosimicrobium cellulans sp. 21
  作者：Ye Yuan、Yanbo Hu、Han Zhang、Jiayi Leng、Fan Li、Xuesong Zhao、Juan Gao、Yifa Zhou

  DOI：10.1016/j.molcatb.2016.06.002

  日期：2016.9

  A multifunctional beta-xylosidase/alpha-L-arabinofuranosidase/beta-glucosidase gene (ccxyl3a) belonging to glycoside hydrolase family 3 (GH3) was cloned from Cellulosimicrobium cellulans sp. 21 and expressed in Escherichia coli BL21 (DE3). The molecular mass of recombinant CcXyl3A was estimated to be approximately 95 kDa. With p-nitrophenyl-beta-D-xyloside (pNP beta Xyl) as a substrate, the purified protein, presented an optimal pH of 8.5 and an optimal temperature of 45 degrees C. Moreover, CcXyl3A was activated in the presence of the metals K+ and Na+. Purified CcXyl3A demonstrated multifunctional activities on pNP beta Xyl, p-nitrophenyl-beta-D-glucoside (pNP beta G1c), and p-nitrophenyl-alpha-L-arabinofuranoside (pNP alpha Araf). The greatest catalytic activity were found on pNP beta Xyl followed by pNPaAraf and pNP beta G1c, respectively. Using xylooligosaccharides as substrate, CcXyl3A completely hydrolyzed xylobiose, xylotriose, xylotetraose and xylohexaose, xylose was the sole product. In addition, CcXyl3A synergistically acted with Thermomyces lanuginosus xylanase in the degradation of beechwood xylan, released xyloses from intermediate xylooligosaccharides produced by T. lanuginosus xylanase. To date, this is the first report to demonstrate the cloning and characterization of a multifunctional GH3 enzyme in C. cellulans that may have applications in hemicellulose degradation. (C) 2016 Elsevier B.V. All rights reserved.
• Characterization of a thermostable, specific GH10 xylanase from Caldicellulosiruptor bescii with high catalytic activity
  作者：Jiao An、Yuan Xie、Yong Zhang、Dongsheng Tian、Shuhao Wang、Guangyu Yang、Yan Feng

  DOI：10.1016/j.molcatb.2015.04.003

  日期：2015.7

  Xylanase (EC 3.2.1.8) is one of the most important enzymes for the biodegradation of xylan. Since many industrial processes utilizing xylanase are operated at elevated temperatures, thermostable xylanases are highly desirable. In the present study, xyn10B gene from thermophilic bacterium Caldicellulosiruptor bescii that encodes a glycoside hydrolase (GH) family 10 xylanase was overexpressed in Escherichia coli and systematically characterized. CbXyn10B exhibited optimal activity at pH 7.2 and 70 degrees C. It had a half-life of about 7.7h at 60 degrees C, and retained over 85% of maximal activity after incubation at pH 4.0-12.0. The activity of this xylanase was not affected by most divalent cations, but inhibited by Fe3+ and Zn2+. CbXyn10B exhibited high activity on beech wood xylan, oat spelt xylan, and birch wood xylan, with specific activities of about 450 U mg(-1). Compared with other GH10 xylanases, CbXyn10B was highly specific for xylan and showed low catalytic efficiency toward sodium carboxymethyl cellulose and p-nitrophenyl-beta-D-xylopyranoside. HPLC analysis of the products released from xylo-oligosaccharides and xylan revealed that xylobiose was the predominant hydrolytic product. The action mode of the enzyme was studied by product analysis, homology modeling and molecular docking to gain an insight into the structural basis for its substrate recognition mechanism. (C) 2015 Elsevier B.V. All rights reserved.
• A Polymer-homologous Series of Crystalline Oligosaccharide Acetates from Xylan Hydrolysate¹
  作者：Roy L. Whistler、Chen-Chuan Tu

  DOI：10.1021/ja01137a027

  日期：1952.9
• Isolation and Properties of a Series of Crystalline Oligosaccharides from Xylan^1,2
  作者：Roy L. Whistler、Chen-Chuan Tu

  DOI：10.1021/ja01134a041

  日期：1952.7
• β-xylosidase from <i>Selenomonas ruminantium</i>: Immobilization, stabilization, and application for xylooligosaccharide hydrolysis
  作者：César Rafael Fanchini Terrasan、Caio Casale Aragon、Douglas Chodi Masui、Benevides Costa Pessela、Gloria Fernandez-Lorente、Eleonora Cano Carmona、Jose Manuel Guisan

  DOI：10.1080/10242422.2016.1247817

  日期：2016.7.3

  The tetrameric -xylosidase from Selenomonas ruminantium is very stable in alkaline pH allowing it to easily immobilize by multipoint covalent attachments on highly activated glyoxyl agarose gels. Initial immobilization resulted only in slight stabilization in relation to the free enzyme, since involvement of all subunits was not achieved. Coating the catalyst with aldehyde-dextran or polyethylenimine, fully stabilized the quaternary structure of the enzyme rendering much more stabilization to the biocatalyst. The catalyst coated with polyethylenimine of molecular weight 1300 is the most stable one exhibiting an interesting half-life of more than 10 days at pH 5.0 and 50 degrees C, being, therefore, 240-fold more stable than free enzyme. Optimum activity was observed in the pH range 4.0-6.0 and at 55 degrees C. The catalyst retained its side activity against p-nitrophenyl -l-arabinofuranoside and it was inhibited by xylose and glucose. Kinetic parameters with p-nitrophenyl -d-xylopyranoside as substrate were V-max 0.20mol.min(-1)mgprot.(-1), K-m 0.45mM, K-cat 0.82s(-1), and K-cat/K-m 1.82s(-1)mM(-1). Xylose release was observed from the hydrolysis of xylooligosaccharides with a decrease in the rate of xylose release by increasing substrate chain-length. Due to the high thermostability and the complete stability after five reuse cycles, the applicability of this biocatalyst in biotechnological processes, such as for the degradation of lignocellulosic biomass, is highly increased.