<β-D-Gal-(1<*>3)>2-β-D-Gal-(1<*>4)-D-Glc

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: <β-D-Gal-(1<*>3)>2-β-D-Gal-(1<*>4)-D-Glc
• 英文别名: β-D-Galp-(1->3)-β-D-Galp-(1->3)-β-D-Galp-(1->4)-D-Glc；3-galactobiosyllactose；Galβ1-3 Galβ1-3Galβ1-4Glc；Gal(b1-3)Gal(b1-3)Gal(b1-4)Glc；(2S,3R,4S,5R,6R)-2-[(2S,3R,4S,5S,6R)-2-[(2R,3S,4S,5R,6S)-3,5-dihydroxy-2-(hydroxymethyl)-6-[(2R,3S,4R,5R)-4,5,6-trihydroxy-2-(hydroxymethyl)oxan-3-yl]oxyoxan-4-yl]oxy-3,5-dihydroxy-6-(hydroxymethyl)oxan-4-yl]oxy-6-(hydroxymethyl)oxane-3,4,5-triol
• 化学式: C₂₄H₄₂O₂₁
• 分子量: 666.585
• InChiKey: JBHRXEIEZLFGPE-UULSNVSMSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  -7.9
• 重原子数：
  45
• 可旋转键数：
  10
• 环数：
  4.0
• sp3杂化的碳原子比例：
  1.0
• 拓扑面积：
  348
• 氢给体数：
  14
• 氢受体数：
  21

反应信息

• 作为反应物：
  描述：

  <β-D-Gal-(1<*>3)>2-β-D-Gal-(1<*>4)-D-Glc 在 glycoside hydrolase 42 enzyme Bga₄₂A from Bifidobacterium longum subsp. infantis ATCC 15697 、 sodium citrate 作用下， 反应 1.5h， 生成 D-吡喃葡萄糖
  参考文献：
  名称：

  Distinct substrate specificities of three glycoside hydrolase family 42  -galactosidases from Bifidobacterium longum subsp. infantis ATCC 15697

  摘要：

  糖苷水解酶家族 42（GH42）包括β-半乳糖苷酶，可催化从不同β-d-半乳糖苷的非还原端释放半乳糖（Gal）。促进健康的益生菌双歧杆菌是人体胃肠道微生物群的重要成员，它们产生的 GH42 酶能利用β-半乳糖苷发挥益生作用。然而，人们对单个 GH42 酶在底物单糖组成、糖苷键和聚合度方面的特异性还缺乏深入了解。对类似于各种牛奶和植物半乳寡糖的天然和合成底物进行动力学分析，区分了益生菌 B. longum subsp. infantis ATCC 15697 编码的三个 GH42 成员 Bga42A、Bga42B 和 Bga42C，并发现位点 +1 上的糖基残基及其与位点 -1 上末端 Gal 的连接是决定特异性的关键因素。因此，Bga42A 更喜欢母乳中的β1-3-半乳糖苷连接，以及其他葡萄糖或 Gal 位于位点 +1 上的β1-3-和β1-6-半乳糖苷。相反，Bga42B 能非常有效地水解 4-半乳糖苷（Galβ1-4Galβ1-4Glc）以及 4-半乳糖双糖（Galβ1-4Gal）和 4-半乳糖三糖（Galβ1-4Galβ1-4Gal）。Bga42C 的特异性与 Bga42B 相似，但活性低一个数量级。根据酶动力学、基因组织和系统发育分析，Bga42C 被认为参与了阿拉伯半乳聚糖衍生寡糖的代谢。三种 GH42 酶的不同动力学特征与 GH42 系统发育树中表示特定支系的独特序列基序相关联，为了解 GH42 亚特异性提供了新的视角。总之，这些数据说明了双歧杆菌对富含β-半乳糖苷的肠道生态位的代谢适应性，并强调了β-半乳糖苷代谢在益生双歧杆菌中的重要性和多样性。

  DOI：

  10.1093/glycob/cwt104
• 作为产物：
  描述：

  Lactose 在 acetate buffer 作用下， 反应 72.0h， 生成 β-D-Galp-(1->3)-D-Glc 、 6-O-β-D-galactopyranosyl-D-galactose 、 别乳糖 、 <β-D-Gal-(1<*>3)>2-β-D-Gal-(1<*>4)-D-Glc
  参考文献：
  名称：

  Primary structure of ten galactosides formed by transglycosylation during lactose hydrolysis by Bifidobacterium bifidum

  摘要：

  Oligosaccharides formed by a transgalactosylation reaction during lactose hydrolysis with Bifidobacterium bifidum were separated into eight fractions by gel-permeation chromatography and their structures studies determined by trimethylsilylation analysis, methylation analysis, f.a.b.-m.s., g.l.c.-m.s. and enzymic hydrolysis as beta-D-Galp-(1----3)-D-Glc, beta-D-Galp-(1----6)-D-Glc, beta-D-Galp-(1----6)-D-Gal, beta-D-Galp-(1----3)-beta-D-Galp-(1----4)-D-Glc, beta-D-Galp-(1----6)[beta-D-Galp-(1----4)]-D-Glc, beta-D-Galp-(1----2)[beta-D-Galp-(1----6)]-D-Glc, beta-D-Galp-(1----3)-beta-D-Galp-(1----3)-beta-D-Galp-(1----4)-D-Glc, beta-D-Galp-(1----3)-beta-D-Galp-(1----3)-beta-D-Galp-(1----3)-beta-D-Ga lp- (1----4)-D-Glc, beta-D-Galp-(1----3)-beta-D-Galp-(1----3)-beta-DGalp-(1----3)-beta -D-Galp-(1----3)-beta-D-Galp-(1----4)-D-Glc, and beta-D-Galp-(1----3)-beta-D-Galp-(1----3)-beta-D-Galp-(1----3)-beta-D-Ga lp-(1----3)-beta-D-G-alp-(1----3) beta-D-Galp-(1----4)-D-Glc.

  DOI：

  10.1016/0008-6215(90)84228-m

文献信息

• Enzymatic α(1→2)-l-fucosylation: investigation of the specificity of the α(1→2)-l-galactosyltransferase from Helix pomatia
  作者：Angela Michelle Scheppokat、Minoru Morita、Joachim Thiem、Hagen Bretting

  DOI：10.1016/s0957-4166(03)00521-4

  日期：2003.8

  The alpha(1-->2)-L-galactosyltransferase from Helix pomatia transfers an L-fucosyl residue from GDP-L-Fucose to a terminal, non-reducin D-galactopyranosyl moiety of an oligosaccharide. The extent of the enzyme's specificity towards the stereochemistry at the D-galactopyranosyl anomeric centre, the site of interglycosidic linkage and the nature of the subterminal oliaosaccharide residue has been investigated using HPAEC-PAD and MALDI-TOF technology. This alpha(1-->2)-L-galactosyltransferase is specific for D-galactopyranosyl beta-linkages, independent of the site of the interglycosidic linkage and aglycone configuration and with limited specificity for the nature of the subterminal sugar residue. (C) 2003 Elsevier Ltd. All rights reserved.
• Distinct substrate specificities of three glycoside hydrolase family 42  -galactosidases from Bifidobacterium longum subsp. infantis ATCC 15697
  作者：A. H. Viborg、T. Katayama、M. Abou Hachem、M. C. Andersen、M. Nishimoto、M. H. Clausen、T. Urashima、B. Svensson、M. Kitaoka

  DOI：10.1093/glycob/cwt104

  日期：2014.2.1

  Glycoside hydrolase family 42 (GH42) includes β-galactosidases catalyzing the release of galactose (Gal) from the non-reducing end of different β-d-galactosides. Health-promoting probiotic bifidobacteria, which are important members of the human gastrointestinal tract microbiota, produce GH42 enzymes enabling utilization of β-galactosides exerting prebiotic effects. However, insight into the specificity of individual GH42 enzymes with respect to substrate monosaccharide composition, glycosidic linkage and degree of polymerization is lagging. Kinetic analysis of natural and synthetic substrates resembling various milk and plant galactooligosaccharides distinguishes the three GH42 members, Bga42A, Bga42B and Bga42C, encoded by the probiotic B. longum subsp. infantis ATCC 15697 and revealed the glycosyl residue at subsite +1 and its linkage to the terminal Gal at subsite −1 to be key specificity determinants. Bga42A thus prefers the β1-3-galactosidic linkage from human milk and other β1-3- and β1-6-galactosides with glucose or Gal situated at subsite +1. In contrast, Bga42B very efficiently hydrolyses 4-galactosyllactose (Galβ1-4Galβ1-4Glc) as well as 4-galactobiose (Galβ1-4Gal) and 4-galactotriose (Galβ1-4Galβ1-4Gal). The specificity of Bga42C resembles that of Bga42B, but the activity was one order of magnitude lower. Based on enzyme kinetics, gene organization and phylogenetic analyses, Bga42C is proposed to act in the metabolism of arabinogalactan-derived oligosaccharides. The distinct kinetic signatures of the three GH42 enzymes correlate to unique sequence motifs denoting specific clades in a GH42 phylogenetic tree providing novel insight into GH42 subspecificities. Overall, the data illustrate the metabolic adaptation of bifidobacteria to the β-galactoside-rich gut niche and emphasize the importance and diversity of β-galactoside metabolism in probiotic bifidobacteria.

  糖苷水解酶家族 42（GH42）包括β-半乳糖苷酶，可催化从不同β-d-半乳糖苷的非还原端释放半乳糖（Gal）。促进健康的益生菌双歧杆菌是人体胃肠道微生物群的重要成员，它们产生的 GH42 酶能利用β-半乳糖苷发挥益生作用。然而，人们对单个 GH42 酶在底物单糖组成、糖苷键和聚合度方面的特异性还缺乏深入了解。对类似于各种牛奶和植物半乳寡糖的天然和合成底物进行动力学分析，区分了益生菌 B. longum subsp. infantis ATCC 15697 编码的三个 GH42 成员 Bga42A、Bga42B 和 Bga42C，并发现位点 +1 上的糖基残基及其与位点 -1 上末端 Gal 的连接是决定特异性的关键因素。因此，Bga42A 更喜欢母乳中的β1-3-半乳糖苷连接，以及其他葡萄糖或 Gal 位于位点 +1 上的β1-3-和β1-6-半乳糖苷。相反，Bga42B 能非常有效地水解 4-半乳糖苷（Galβ1-4Galβ1-4Glc）以及 4-半乳糖双糖（Galβ1-4Gal）和 4-半乳糖三糖（Galβ1-4Galβ1-4Gal）。Bga42C 的特异性与 Bga42B 相似，但活性低一个数量级。根据酶动力学、基因组织和系统发育分析，Bga42C 被认为参与了阿拉伯半乳聚糖衍生寡糖的代谢。三种 GH42 酶的不同动力学特征与 GH42 系统发育树中表示特定支系的独特序列基序相关联，为了解 GH42 亚特异性提供了新的视角。总之，这些数据说明了双歧杆菌对富含β-半乳糖苷的肠道生态位的代谢适应性，并强调了β-半乳糖苷代谢在益生双歧杆菌中的重要性和多样性。
• Primary structure of ten galactosides formed by transglycosylation during lactose hydrolysis by Bifidobacterium bifidum
  作者：Vincent Dumortier、Jean Montreuil、Stéphane Bouquelet

  DOI：10.1016/0008-6215(90)84228-m

  日期：1990.6

  Oligosaccharides formed by a transgalactosylation reaction during lactose hydrolysis with Bifidobacterium bifidum were separated into eight fractions by gel-permeation chromatography and their structures studies determined by trimethylsilylation analysis, methylation analysis, f.a.b.-m.s., g.l.c.-m.s. and enzymic hydrolysis as beta-D-Galp-(1----3)-D-Glc, beta-D-Galp-(1----6)-D-Glc, beta-D-Galp-(1----6)-D-Gal, beta-D-Galp-(1----3)-beta-D-Galp-(1----4)-D-Glc, beta-D-Galp-(1----6)[beta-D-Galp-(1----4)]-D-Glc, beta-D-Galp-(1----2)[beta-D-Galp-(1----6)]-D-Glc, beta-D-Galp-(1----3)-beta-D-Galp-(1----3)-beta-D-Galp-(1----4)-D-Glc, beta-D-Galp-(1----3)-beta-D-Galp-(1----3)-beta-D-Galp-(1----3)-beta-D-Ga lp- (1----4)-D-Glc, beta-D-Galp-(1----3)-beta-D-Galp-(1----3)-beta-DGalp-(1----3)-beta -D-Galp-(1----3)-beta-D-Galp-(1----4)-D-Glc, and beta-D-Galp-(1----3)-beta-D-Galp-(1----3)-beta-D-Galp-(1----3)-beta-D-Ga lp-(1----3)-beta-D-G-alp-(1----3) beta-D-Galp-(1----4)-D-Glc.