D-galactaro-1,4-lactone(1-)

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 内酯类
• 英文名称: D-galactaro-1,4-lactone(1-)
• 英文别名: (2S)-2-[(2R,3R,4R)-3,4-dihydroxy-5-oxooxolan-2-yl]-2-hydroxyacetate
• 化学式: C6H7O7-
• 分子量: 191.12
• InChiKey: XECPAIJNBXCOBO-LKELSTGYSA-M

计算性质

• 辛醇/水分配系数(LogP)：
  -1.1
• 重原子数：
  13
• 可旋转键数：
  1
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.67
• 拓扑面积：
  127
• 氢给体数：
  3
• 氢受体数：
  7

反应信息

• 作为反应物：
  描述：

  D-galactaro-1,4-lactone(1-) 生成 2,3-Dihydroxy-5-oxo-hexanedioate 、 氢(+1)阳离子
  参考文献：
  名称：

  根癌农杆菌中参与果胶降解的 D-半乳糖酰-1,4-内酯环异构酶的纯化、结晶和结构解析。

  摘要：

  果胶存在于植物细胞壁中，通常被作为废物丢弃。许多研究小组有兴趣将这种生物质废物流重新用于燃料和大宗化学品的生产。这种多糖的主要单体亚基是 D-半乳糖醛酸，这是一种六碳酸糖，可通过一些细菌（包括根癌农杆菌）通过五步途径降解为中心代谢中间体。在该途径的第三步中，D-半乳糖苷-1,4-内酯被烯醇酶超家族的扁桃酸消旋酶亚组的成员转化为 2-酮-3-脱氧-L-苏式-六酸酯，具有以下新活性：超家族。确定了该酶的 1.6 Å 分辨率结构，揭示了整体修饰的 (β/α) 7 β TIM 桶结构域，这是该超家族的标志。D-Galactaro-1,4-内酯手动对接至位于 N 端盖结构域和 C 端桶结构域之间界面的活性位点。根据内酯在活性位点中的位置，Lys166 预计是负责提取 α 质子的活性位点碱基。预计活性位点另一侧的 His296 是在内酯环打开时向 β 碳提供质子的一般酸。内酯环似乎通过与 Trp298

  DOI：

  10.1107/s2053230x15023286
• 作为产物：
  描述：

  D-galactaro-1,5-lactone(1-) 生成 D-galactaro-1,4-lactone(1-)
  参考文献：
  名称：

  Galactaro δ-Lactone Isomerase: Lactone Isomerization by a Member of the Amidohydrolase Superfamily

  摘要：

  Agrobacterium tumefaciens strain C58 can utilize D-galacturonate as a sole source of carbon via a pathway in which the first step is oxidation of D-galacturonate to D-galactaro-1,5-lactone. We have identified a novel enzyme, D-galactarolactone isomerase (GLI), that catalyzes the isomerizaton of D-galactaro-1,5-lactone to D-galactaro-1,4-lactone. GLI; a member of the functionally diverse amidohydrolase superfamily, is a homologue of LigI that catalyzes the hydrolysis of 2-pyrone-4,6-dicarboxylate in lignin degradation. The ability of GLI to catalyze lactone isomerization instead of hydrolysis can be explained by the absence of the general basic catalysis used by 2-pyrone-4,6-dicarbolcylate lactonase.

  DOI：

  10.1021/bi5000492

文献信息

• Characterization of a novel Agrobacterium tumefaciens Galactarolactone Cycloisomerase Enzyme for Direct Conversion of d-Galactarolactone to 3-Deoxy-2-keto-l-threo-hexarate
  作者：Martina Andberg、Hannu Maaheimo、Harry Boer、Merja Penttilä、Anu Koivula、Peter Richard

  DOI：10.1074/jbc.m111.335240

  日期：2012.5

  Microorganisms use different pathways for D-galacturonate catabolism. In the known microbial oxidative pathway, D-galacturonate is oxidized to D-galactarolactone, the lactone hydrolyzed to galactarate, which is further converted to 3-deoxy-2-keto-hexarate and alpha-ketoglutarate. We have shown recently that Agrobacterium tumefaciens strain C58 contains an uronate dehydrogenase (At Udh) that oxidizes D-galacturonic acid to D-galactarolactone. Here we report identification of a novel enzyme from the same A. tumefaciens strain, which we named Galactarolactone cycloisomerase (At Gci) (E.C. 5.5.1.-), for the direct conversion of the D-galactarolactone to 3-deoxy-2-keto-hexarate. The At Gci enzyme is 378 amino acids long and belongs to the mandelate racemase subgroup in the enolase superfamily. At Gci was heterologously expressed in Escherichia coli, and the purified enzyme was found to exist as an octameric form. It is active both on D-galactarolactone and D-glucarolactone, but does not work on the corresponding linear hexaric acid forms. The details of the reaction mechanism were further studied by NMR and optical rotation demonstrating that the reaction product of At Gci from D-galactaro-1,4-lactone and D-glucaro-1,4-lactone conversion is in both cases the L-threo form of 3-deoxy-2-keto-hexarate.
• Galactaro δ-Lactone Isomerase: Lactone Isomerization by a Member of the Amidohydrolase Superfamily
  作者：Jason T. Bouvier、Fiona P. Groninger-Poe、Matthew Vetting、Steven C. Almo、John A. Gerlt

  DOI：10.1021/bi5000492

  日期：2014.2.4

  Agrobacterium tumefaciens strain C58 can utilize D-galacturonate as a sole source of carbon via a pathway in which the first step is oxidation of D-galacturonate to D-galactaro-1,5-lactone. We have identified a novel enzyme, D-galactarolactone isomerase (GLI), that catalyzes the isomerizaton of D-galactaro-1,5-lactone to D-galactaro-1,4-lactone. GLI; a member of the functionally diverse amidohydrolase superfamily, is a homologue of LigI that catalyzes the hydrolysis of 2-pyrone-4,6-dicarboxylate in lignin degradation. The ability of GLI to catalyze lactone isomerization instead of hydrolysis can be explained by the absence of the general basic catalysis used by 2-pyrone-4,6-dicarbolcylate lactonase.
• Purification, crystallization and structural elucidation of<scp>D</scp>-galactaro-1,4-lactone cycloisomerase from<i>Agrobacterium tumefaciens</i>involved in pectin degradation
  作者：Matthew W. Vetting、Jason T. Bouvier、John A. Gerlt、Steven C. Almo

  DOI：10.1107/s2053230x15023286

  日期：2016.1.1

  six‐carbon acid sugar that is degraded in a five‐step pathway to central metabolic intermediates by some bacteria, including Agrobacterium tumefaciens. In the third step of the pathway, D‐galactaro‐1,4‐lactone is converted to 2‐keto‐3‐deoxy‐L‐threo‐hexarate by a member of the mandelate racemase subgroup of the enolase superfamily with a novel activity for the superfamily. The 1.6 Å resolution structure

  果胶存在于植物细胞壁中，通常被作为废物丢弃。许多研究小组有兴趣将这种生物质废物流重新用于燃料和大宗化学品的生产。这种多糖的主要单体亚基是 D-半乳糖醛酸，这是一种六碳酸糖，可通过一些细菌（包括根癌农杆菌）通过五步途径降解为中心代谢中间体。在该途径的第三步中，D-半乳糖苷-1,4-内酯被烯醇酶超家族的扁桃酸消旋酶亚组的成员转化为 2-酮-3-脱氧-L-苏式-六酸酯，具有以下新活性：超家族。确定了该酶的 1.6 Å 分辨率结构，揭示了整体修饰的 (β/α) 7 β TIM 桶结构域，这是该超家族的标志。D-Galactaro-1,4-内酯手动对接至位于 N 端盖结构域和 C 端桶结构域之间界面的活性位点。根据内酯在活性位点中的位置，Lys166 预计是负责提取 α 质子的活性位点碱基。预计活性位点另一侧的 His296 是在内酯环打开时向 β 碳提供质子的一般酸。内酯环似乎通过与 Trp298