4-O-Methyl-D-glucuronsaeure | 6778-34-3

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: 4-O-Methyl-D-glucuronsaeure
• 英文别名: 4-O-methyl-D-glucuronic acid；4-O-Methylglucopyranuronic acid；(2S,3S,4R,5R)-4,5,6-trihydroxy-3-methoxyoxane-2-carboxylic acid
• CAS: 6778-34-3
• 化学式: C₇H₁₂O₇
• 分子量: 208.168
• InChiKey: WGLLPAPKWFDHHV-XZKARQSESA-N

计算性质

• 辛醇/水分配系数(LogP)：
  -2.4
• 重原子数：
  14
• 可旋转键数：
  2
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.86
• 拓扑面积：
  116
• 氢给体数：
  4
• 氢受体数：
  7

反应信息

• 作为反应物：
  描述：

  4-O-Methyl-D-glucuronsaeure 在 钾硼氢 、 Dowex-50 X-8 (H⁽¹⁺⁾) resin 作用下， 以 水 为溶剂， 反应 20.0h， 生成 4-O-methyl-D-glucopyranose
  参考文献：
  名称：

  黄麻纤维中的木质素-木聚糖酯键合

  摘要：

  摘要用硼氢化钾水溶液处理黄麻纤维（I）可得到灰白色纤维（II）（含原始木质素的77％）和水溶性木质素-碳水化合物复合物（III）。在水解时，II和III都提供了新的糖，即4-O-甲基-d-葡萄糖，与与I相同的酸性和中性糖组分混合。从I和II制备的全纤维素的碱萃取得到粗制的d-木聚糖，其与氢氧化钡水溶液分馏，得到两个富集的d-木聚糖，每100个木糖基残基分别含有15.9和10.5单位的糖醛酸侧链。这些结果表明，I中d-木聚糖的酸性侧链的约34％通过酯键与木质素连接。

  DOI：

  10.1016/s0008-6215(00)85597-4
• 作为产物：
  描述：

  6-O-(4-O-Methyl-β-D-glucopyranosyluronsaeure)-D-galactose 在 serAnGlc*of*Aspergillus*niger*van*Tieghem*(ATCC*22343) 作用下， 以 acetate buffer 为溶剂， 生成 4-O-Methyl-D-glucuronsaeure
  参考文献：
  名称：

  Properties of family 79 β-glucuronidases that hydrolyze β-glucuronosyl and 4-O-methyl-β-glucuronosyl residues of arabinogalactan-protein

  摘要：

  The carbohydrate moieties of arabinogalactan-proteins (AGPs), which are mainly composed of Gal, L-Ara, GlcA, and 4Me-GlcA residues, are essential for the physiological functions of these proteoglycans in higher plants. For this study, we have identified two genes encoding family 79 beta-glueuronidases, designated AnGlcAase and NcGlcAase, in Aspergillus niger and Neurospora crassa, respectively, based on the amino acid sequence of a native beta-glucuronidase purified from a commercial pectolytic enzyme preparation from A. niger. Although the deduced protein sequences of AnGlcAase and NcGlcAase were highly similar, the recombinant enzymes expressed in Pichia pastoris exhibited distinct substrate specificity toward 4-Me-GlcA residues of AGPs: recombinant ADGlcAase (rAnGlcAase) substantially liberated both GlcA and 4-Me-GlcA residues from radish AGPs, whereas recombinant NcGlcAase (rNcGlcAase) activity on the 4-Me-GlcA residues of AGPs was very low. Maximum activity of rAnGlcAase hydrolyzing PNP beta-GlcA occurred at pH 3.0-4.0, whereas the maximum rNcGlcAase activity was at pH 6.0. The apparent K. values of rAnGlcAase were 30.4 mu M for PNP beta-GlcA and 422 mu M for beta-GIcA-(1 -> 6)-Gal, and those of rNcGlcAase were 38.3 mu M and 378 mu M, respectively. Similar to the native enzyme, rAnGlcAase was able to catalyze the transglycosylation of GlcA residues from PNP beta-GlcA to various monosaccharide acceptors such as Glc, Gal, and Xyl. We propose that both AnGlcAase and NcGlcAase are instances of a novel type of beta-glucuronidase with the capacity to hydrolyze beta-GlcA and 4-Me-beta-GlcA residues of AGPs, although they differ significantly in their preferences. (c) 2008 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.carres.2008.03.004

文献信息

• Fungal Glucuronoyl Esterases and Substrate Uronic Acid Recognition
  作者：Miroslava ĎURANOVÁ、Ján HIRSCH、Katarína KOLENOVÁ、Peter BIELY

  DOI：10.1271/bbb.90486

  日期：2009.11.23

  Glucuronoyl esterases are enzymes involved in microbial plant cell-wall degradation. In this study we purified and characterized two recombinant Phanerochaete chrysosporium glucuronoyl esterases, PcGE1 and PcGE2. The catalytic activity of these and previously described glucuronoyl esterases was investigated on new synthetic substrates, methyl esters of uronic acids and their glycosides, prepared by esterification with ethereal diazomethane.The data obtained indicate that the enzymes hydrolyzed efficiently not only esters of 4-O-methyl-d-glucuronic acid, but also methyl esters of d-glucuronic acid carrying a 4-nitrophenyl aglycon. Moreover, the fact that they did not recognize the 4-epimers of these compounds, the d-galacturonic acid derivatives, supports the hypothesis that these carbohydrate esterases attack ester linkages between 4-O-methyl-d-glucuronic acid of glucuronoxylan and lignin alcohols.

  葡萄糖醛酸酯酶是一种参与微生物植物细胞壁降解的酶。在这项研究中，我们纯化并鉴定了两种重组的 Phanerochaete chrysosporium 葡萄醛酰酯酶 PcGE1 和 PcGE2。获得的数据表明，这些酶不仅能有效地水解 4-O-甲基-d-葡萄糖醛酸酯，还能有效地水解带有 4-硝基苯苷元的 d-葡萄糖醛酸甲酯。此外，它们不能识别这些化合物的 4-表聚体，即 d-半乳糖醛酸衍生物，这一事实支持了这样一种假设，即这些碳水化合物酯酶能攻击葡萄糖醛酸的 4-O-甲基-d-葡萄糖醛酸与木质素醇之间的酯连接。