2-Acetamido-5-oxopentanoate

• 分子结构分类: 有机化合物 - 有机酸及其衍生物 - 羧酸及其衍生物
• 英文名称: 2-Acetamido-5-oxopentanoate
• 英文别名: (2S)-2-acetamido-5-oxopentanoate
• 化学式: C7H10NO4-
• 分子量: 172.16
• InChiKey: BCPSFKBPHHBDAI-LURJTMIESA-M

计算性质

• 辛醇/水分配系数(LogP)：
  -0.4
• 重原子数：
  12
• 可旋转键数：
  4
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.57
• 拓扑面积：
  86.3
• 氢给体数：
  1
• 氢受体数：
  4

反应信息

• 作为反应物：
  描述：

  水 、 2-Acetamido-5-oxopentanoate 生成 乙酸盐 、 glutamate γ-semialdehyde
  参考文献：
  名称：

  Proline Excretion and Indirect Suppression in Escherichia coli and Salmonella typhimurium

  摘要：

  在大肠杆菌K-12、鼠伤寒沙门氏菌LT7和其他一些肠道细菌株中，脯氨酸生物合成的最后一步是被调节的，以便不排出任何脯氨酸，即使向培养基中添加过量的Δ1-吡咯烷酮-5-羧酸，即脯氨酸的直接前体。在脯氨酸辅助营养物在脯氨酸生物合成的早期阻滞（proA或proB）的突变体中，复性往往是由精氨酸途径中的突变引起的，该突变将N-乙酰谷氨酸γ-半醛转向脯氨酸合成，从而绕过proA或proB的阻滞。在这样的双突变体（proAB，argD）中，脯氨酸合成的最后一步似乎是未经调节的，因为脯氨酸被排出。反馈抑制和精氨酸途径的抑制克服了间接抑制（恢复Pro-表型），但脯氨酸调节没有恢复；当给予外源性的Δ1-吡咯烷酮-5-羧酸时，双突变体仍然排出脯氨酸。还描述了一类由于argD突变而产生的脯氨酸类似物耐药突变体。

  DOI：

  10.1128/jb.118.3.928-934.1974
• 作为产物：
  描述：

  2-氧代-戊二酸离子(2-) 、 (S)-2-乙酰氨基-5-氨基戊酸 生成 2-氨基戊二酸酯 、 2-Acetamido-5-oxopentanoate
  参考文献：
  名称：

  鼠伤寒沙门氏菌生物合成的N-乙酰鸟氨酸氨基转移酶的结构：底物特异性和抑制剂结合的研究。

  摘要：

  乙酰基鸟氨酸氨基转移酶（AcOAT）是精氨酸代谢中的关键酶之一，在L-谷氨酸的存在下催化N-乙酰谷氨酸半醛向N-乙酰鸟氨酸（AcOrn）的转化。它属于吡ido醛5'-磷酸（PLP）依赖型酶的I型II类家族。大肠杆菌生物合成AcOAT（eAcOAT）还催化N-琥珀酰-L-2-氨基-6-氧肟酸酯转化为N-琥珀酰-L，L-二氨基庚二酸酯，这是赖氨酸生物合成的步骤之一。鉴于AcOAT在赖氨酸和精氨酸生物合成中的关键作用，开始对鼠伤寒沙门氏菌（sAcOAT）的酶进行结构研究。用纯化的sAcOAT测定的K（m）和k（cat）/ K（m）值表明，该酶对AcOrn的亲和力比对鸟氨酸（Orn）的亲和力高得多，并且比eAcOAT更有效。sAcOAT被加巴胆碱（Gcn）抑制，抑制常数（K（i））为7 microM，二级速率常数（k（2））为0.16 mM（-1）s（-1）。sAcOAT以无配体形式结晶，并在Gc

  DOI：

  10.1002/prot.21567

文献信息

• Cloning and characterization of the aru genes encoding enzymes of the catabolic arginine succinyltransferase pathway in Pseudomonas aeruginosa
  作者：Y Itoh

  DOI：10.1128/jb.179.23.7280-7290.1997

  日期：1997.12

  The arginine succinyltransferase (AST) pathway is the major arginine and ornithine utilization (aru) pathway under aerobic conditions in Pseudomonas aeruginosa. A 26-kb DNA fragment of the P. aeruginosa PAO1 chromosome carrying the regulatory argR gene and the aru structural gene cluster was cloned. Complementation tests and nucleotide sequence data established the locations of the argR, aruC, aruF, aruG, aruD, aruB, and aruE genes, in that order. The aruR, aruC, aruD, aruB, and aruE genes specify the ArgR regulatory protein, N2-succinylornithine 5-aminotransferase, N-succinylglutamate 5-semialdehyde dehydrogenase, N2-succinylarginine dihydrolase, and N-succinylglutamate desuccinylase, respectively, and the aruF and aruG genes encode the subunits (AruAI and AruAII) of arginine and ornithine N2-succinyltransferases. Furthermore, in vivo analysis of transcriptional aru fusions and of polar insertion mutations located at different sites in the aru cluster indicated the presence of three transcriptional units which are controlled by ArgR. The aruCFGDB genes appear to form an operon transcribed from a promoter upstream of aruC, whereas aruE has its own promoter. The argR gene, which is located upstream of the aruCFGDB operon, is a member of another (aot) operon coding for arginine transport genes. The deduced amino acid sequences of the AST enzymes were compared to those of homologous proteins of Escherichia coli specified by the ast genes lying in the chromosome region from 39.2 to 39.5 min (Kohara clone 327; GenBank/EMBL/DDJB accession no. D90818). The overall organization of the aru and ast genes in both organisms is similar, with the exception that E. coli appears to have a single AST gene.

  辅酶A精氨酸琥珀酰转移酶（AST）途径是铜绿假单胞菌在有氧条件下的主要精氨酸和鸟氨酸利用（aru）途径。克隆了Pseudomonas aeruginosa PAO1染色体的26 kb DNA片段，其中包含调节基因argR和aru结构基因簇。补充试验和核苷酸序列数据确定了argR、aruC、aruF、aruG、aruD、aruB和aruE基因的位置，顺序为上述。aruR、aruC、aruD、aruB和aruE基因指定了ArgR调节蛋白、N2-琥珀酰鸟氨酸5-氨基转移酶、N-琥珀酰谷氨酸5-半醛脱氢酶、N2-琥珀酰精氨酸双氢酶和N-琥珀酰谷氨酸脱琥珀酰酶，aruF和aruG基因编码精氨酸和鸟氨酸N2-琥珀酰转移酶的亚基（AruAI和AruAII）。此外，对位于aru簇不同位点的极性插入突变和转录aru融合体的体内分析表明，存在由ArgR控制的三个转录单元。aruCFGDB基因似乎形成一个从aruC上游启动子转录的operon，而aruE有自己的启动子。位于aruCFGDB operon上游的argR基因是编码精氨酸转运基因的另一个（aot）operon的成员。将AST酶的推导氨基酸序列与Escherichia coli中的ast基因指定的同源蛋白质进行比较，后者位于39.2到39.5分钟的染色体区域（Kohara clone 327; GenBank/EMBL/DDJB accession no. D90818）。两种生物中aru和ast基因的整体组织相似，唯一的区别是E. coli似乎只有单个AST基因。
• Crystal Structure of N-acetyl-γ-glutamyl-phosphate Reductase from Mycobacterium tuberculosis in Complex with NADP+
  作者：Leonid T. Cherney、Maia M. Cherney、Craig R. Garen、Chunying Niu、Fatemeh Moradian、Michael N.G. James

  DOI：10.1016/j.jmb.2007.01.033

  日期：2007.4

  docking of the substrate to the enzyme has been performed using the present structure of the MtbAGPR/NADP(+) complex. It reveals that residues His217 and His219 could form hydrogen bonds with the docked substrate. In addition, an ion pair could form between the substrate phosphate group and the guanidinium group of Arg114. These interactions optimally place and orient the substrate for subsequent nucleophilic

  酶N-乙酰基-γ-谷氨酰磷酸还原酶（AGPR）催化烟酰胺腺嘌呤二核苷酸磷酸（NADPH）依赖性的N-乙酰基-γ-谷氨酰磷酸还原为N-乙酰基谷氨酸-γ-半醛还原磷酸化反应。该反应是精氨酸生物合成途径的一部分，对于某些微生物和植物，特别是对于结核分枝杆菌（Mtb）而言，精氨酸生物合成途径必不可少。解决和分析了空间群P2（1）2（1）2（1）和C2中的载脂蛋白MtbAGPR的结构以及与辅因子NADP（+）结合的MtbAGPR的结构。每个MtbAGPR亚基均由alpha / beta和alpha + beta域组成；NADP（+）绑定在它们之间的缝隙中。已经检查了酶和辅因子之间的氢键和疏水接触。载脂蛋白和结合的酶结构的比较已经揭示了NADP（+）结合后MtbAGPR的构象变化。即，环（Leu88至His92）移动超过5A以在空间上将辅因子的腺嘌呤部分限制在疏水口袋中。为了鉴定MtbAGPR中重要的催化残基，已经使用MtbAGPR
• Suppression of Proline Requirement of <i>proA</i> and <i>proAB</i> Deletion Mutants in <i>Salmonella typhimurium</i> by Mutation to Arginine Requirement
  作者：Tseng-Tong Kuo、B. A. D. Stocker

  DOI：10.1128/jb.98.2.593-598.1969

  日期：1969.5

  Salmonella typhimurium LT7 proA and proAB deletion mutants. Suppression resulted from mutation at argG, which specifies N(alpha)-acetylornithine delta-transaminase. In the absence of exogenous arginine, deficiency of this enzyme would cause derepression of the arginine pathway and accumulation of N-acetylglutamic gamma-semialdehyde. N-acetylglutamic gamma-semialdehyde, if deacetylated, would produce

  通过自鼠伤寒沙门氏菌LT7 proA和proAB缺失突变体的自发突变获得了能够在没有脯氨酸的情况下生长的十一个变体（缺少精氨酸）。抑制是由argG突变引起的，该突变指定Nα-乙酰鸟氨酸δ-转氨酶。在没有外源精氨酸的情况下，该酶的缺乏会导致精氨酸途径的阻遏和N-乙酰谷氨酸γ-半醛的积累。N-乙酰谷氨酸γ-半醛如果被脱乙酰基，将产生谷氨酸γ-半醛，这是脯氨酸前体，其谷氨酸合成被proA和proAB突变体阻断。如果不提供精氨酸，所有突变体仅缓慢生长（有些非常缓慢）。八个突变体的超声处理制剂没有可测量的乙酰鸟氨酸δ-转氨酶活性，但是三个对精氨酸依赖性最低的突变体的野生型活性分别为0.11、0.28和1.48。据推测，它们的酶至少在体内具有较低的比活性。噬菌体P22共转导了argG和strA。遗传分析表明，具有比野生型更高的体外酶活性的突变体，其对精氨酸的依赖程度较小，是其argG等位基因的特征，而
• Role of the yeast acetyltransferase Mpr1 in oxidative stress: Regulation of oxygen reactive species caused by a toxic proline catabolism intermediate
  作者：Michiyo Nomura、Hiroshi Takagi

  DOI：10.1073/pnas.0403349101

  日期：2004.8.24

  The MPR1 gene, which is found in the Σ1278b strain but is not present in the sequenced laboratory strain S288C, of the budding yeast Saccharomyces cerevisiae encodes a previously uncharacterized N -acetyltransferase that detoxifies the proline analogue azetidine-2-carboxylate (AZC). However, it is unlikely that AZC is a natural substrate of Mpr1 because AZC is found only in some plant species. In our search for the physiological function of Mpr1, we found that mpr1 -disrupted cells were hypersensitive to oxidative stresses and contained increased levels of reactive oxygen species (ROS). In contrast, overexpression of MPR1 leads to an increase in cell viability and a decrease in ROS level after oxidative treatments. These results indicate that Mpr1 can reduce intracellular oxidation levels. Because put2 -disrupted yeast cells lacking Δ ¹ -pyrroline-5-carboxylate (P5C) dehydrogenase have increased ROS, we examined the role of Mpr1 in put2 -disrupted strains. When grown on media containing urea and proline as the nitrogen source, put2 -distrupted cells did not grow as well as WT cells and accumulated intracellular levels of P5C that were first detected in yeast cells and ROS. On the other hand, put2 -disrupted cells that overexpressed MPR1 had considerably lower ROS levels. In vitro studies with bacterially expressed Mpr1 demonstrated that Mpr1 can acetylate P5C, or, more likely, its equilibrium compound glutamtate-γ-semialdehyde, at neutral pH. These results suggest that the proline catabolism intermediate P5C is toxic to yeast cells because of the formation of ROS, and Mpr1 regulates the ROS level under P5C-induced oxidative stress.

  在酿酒酵母Saccharomyces cerevisiae的Σ1278b菌株中发现了MPR1基因，但在测序的实验室菌株S288C中不存在，该基因编码一个以前未被表征的N-乙酰转移酶，可以解毒脯氨酸类似物azetidine-2-carboxylate（AZC）。然而，AZC只存在于一些植物物种中，因此不太可能是Mpr1的天然底物。在寻找Mpr1的生理功能时，我们发现mpr1缺失的细胞对氧化应激非常敏感，并且含有增加的活性氧（ROS）水平。相反，MPR1的过表达导致细胞存活率增加，并且在氧化处理后ROS水平下降。这些结果表明Mpr1可以降低细胞内氧化水平。由于缺乏Δ1-吡咯烷酮-5-羧酸（P5C）脱氢酶的put2缺失酵母细胞具有增加的ROS，因此我们研究了Mpr1在put2缺失菌株中的作用。在含有尿素和脯氨酸作为氮源的培养基上生长时，put2缺失细胞的生长不如WT细胞，并且在酵母细胞和ROS中首次检测到细胞内P5C的积累。另一方面，过表达MPR1的put2缺失细胞具有明显较低的ROS水平。与大肠杆菌表达的Mpr1的体外研究表明，Mpr1可以在中性pH下乙酰化P5C，或者更可能是其平衡化合物谷氨酸-γ半醛。这些结果表明，由于ROS的形成，脯氨酸代谢中间产物P5C对酵母细胞有毒，并且Mpr1在P5C诱导的氧化应激下调节ROS水平。
• An antioxidative mechanism mediated by the yeast N-acetyltransferase Mpr1: oxidative stress-induced arginine synthesis and its physiological role
  作者：Akira Nishimura、Tetsuya Kotani、Yu Sasano、Hiroshi Takagi

  DOI：10.1111/j.1567-1364.2010.00650.x

  日期：2010.9

  Saccharomyces cerevisiaeΣ1278b has the MPR1 gene encoding the N-acetyltransferase Mpr1 that acetylates the proline metabolism intermediate Δ1-pyrroline-5-carboxylate (P5C)/glutamate-γ-semialdehyde (GSA) in vitro. In addition, Mpr1 protects cells from various oxidative stresses by regulating the levels of intracellular reactive oxygen species (ROS). However, the relationship between P5C/GSA acetylation and antioxidative mechanism involving Mpr1 remains unclear. Here, we report the synthesis of oxidative stress-induced arginine via P5C/GSA acetylation catalyzed by Mpr1. Gene disruption analysis revealed that Mpr1 converts P5C/GSA into N-acetyl-GSA for arginine synthesis in the mitochondria, indicating that Mpr1 mediates the proline and arginine metabolic pathways. More importantly, Mpr1 regulate ROS generation by acetylating toxic P5C/GSA. Under oxidative stress conditions, the transcription of PUT1 encoding the proline oxidase Put1 and MPR1 was strongly induced, and consequently, the arginine content was significantly increased. We also found that two deletion mutants (Δmpr1/2 and Δput1) were more sensitive to high-temperature stress than the wild-type strain, but that direct treatment with arginine restored the cell viability of these mutants. These results suggest that Mpr1-dependent arginine synthesis confers stress tolerance. We propose an antioxidative mechanism that is involved in stress-induced arginine synthesis requiring Mpr1 and Put1.

  酿酒酵母Σ1278b具有MPR1基因，编码N-乙酰转移酶Mpr1，该酶在体外乙酰化脯氨酸代谢中间产物Δ1-吡咯啉-5-羧酸（P5C）/谷氨酸-γ-半醛（GSA）。此外，Mpr1通过调节细胞内活性氧（ROS）的水平来保护细胞免受各种氧化应激。然而，P5C/GSA乙酰化和抗氧化机制（涉及Mpr1）之间的关系尚不清楚。在这里，我们报道了通过Mpr1催化P5C/GSA乙酰化合成氧化应激诱导的精氨酸。基因破坏分析表明，Mpr1将P5C/GSA转化为N-乙酰基-GSA，用于线粒体中的精氨酸合成，这表明Mpr1介导了脯氨酸和精氨酸的代谢途径。更重要的是，Mpr1通过乙酰化有毒的P5C/GSA来调节ROS的产生。在氧化应激条件下，编码脯氨酸氧化酶Put1和MPR1的PUT1的转录被强烈诱导，因此精氨酸含量显着增加。我们还发现，两个缺失突变体（Δmpr1/2和Δput1）比野生型菌株对高温应激更敏感，但直接用精氨酸处理可以恢复这些突变