acetoacetyl-CoA(4-)

• 分子结构分类: 有机化合物 - 脂质和类脂质分子 - 脂肪酰基
• 英文名称: acetoacetyl-CoA(4-)
• 英文别名: [(2R,3S,4R,5R)-5-(6-aminopurin-9-yl)-4-hydroxy-2-[[[[(3R)-3-hydroxy-2,2-dimethyl-4-oxo-4-[[3-oxo-3-[2-(3-oxobutanoylsulfanyl)ethylamino]propyl]amino]butoxy]-oxidophosphoryl]oxy-oxidophosphoryl]oxymethyl]oxolan-3-yl] phosphate
• 化学式: C25H36N7O18P3S-4
• 分子量: 847.6
• InChiKey: OJFDKHTZOUZBOS-CITAKDKDSA-J

计算性质

• 辛醇/水分配系数(LogP)：
  -6.1
• 重原子数：
  54
• 可旋转键数：
  21
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.64
• 拓扑面积：
  417
• 氢给体数：
  5
• 氢受体数：
  23

反应信息

• 作为反应物：
  描述：

  左旋肉碱 、 acetoacetyl-CoA(4-) 生成 coenzyme A 、 (R)-acetoacetylcarnitine
  参考文献：
  名称：

  Substrate specificity of human carnitine acetyltransferase: Implications for fatty acid and branched-chain amino acid metabolism

  摘要：

  Carnitine acyltransferases catalyze the reversible conversion of acyl-CoAs into acylcarnitine esters. This family includes the mitochondrial enzymes carnitine palmitoyltransferase 2 (CPT2) and carnitine acetyltransferase (CrAT). CPT2 is part of the carnitine shuttle that is necessary to import fatty acids into mitochondria and catalyzes the conversion of acylcarnitines into acyl-CoAs. In addition, when mitochondrial fatty acid P-oxidation is impaired, CPT2 is able to catalyze the reverse reaction and converts accumulating long- and medium-chain acyl-CoAs into acylcarnitines for export from the matrix to the cytosol. However, CPT2 is inactive with short-chain acyl-CoAs and intermediates of the branched-chain amino acid oxidation pathway (BCAAO). In order to explore the origin of short-chain and branched-chain acylcarnitines that may accumulate in various organic acidemias, we performed substrate specificity studies using purified recombinant human CrAT. Various saturated, unsaturated and branched-chain acyl-CoA esters were tested and the synthesized acylcarnitines were quantified by ESI-MS/MS. We show that CrAT converts short- and medium-chain acyl-CoAs (C2 to C10-00A), whereas no activity was observed with long-chain species. Trans-2-enoyl-00A intermediates were found to be poor substrates for this enzyme. Furthermore, CrAT turned out to be active towards some but not all the BCAAO intermediates tested and no activity was found with dicarboxylic acyl-CoA esters. This suggests the existence of another enzyme able to handle the acyl-CoAs that are not substrates for CrAT and CPT2, but for which the corresponding acylcarnitines are well recognized as diagnostic markers in inborn errors of metabolism. (C) 2013 Elsevier B.V. All rights reserved.

  DOI：

  10.1016/j.bbadis.2013.02.012
• 作为产物：
  描述：

  (2R)-N-[3-(2-acetylsulfanylethylimino)-3-oxidopropyl]-4-[[[(2R,3S,4R,5R)-5-(6-aminopurin-9-yl)-4-hydroxy-3-phosphonatooxyoxolan-2-yl]methoxy-hydroxyphosphoryl]oxy-hydroxyphosphoryl]oxy-2-hydroxy-3,3-dimethylbutanimidate 生成 acetoacetyl-CoA(4-) 、 coenzyme A
  参考文献：
  名称：

  人类线粒体乙酰乙酰辅酶A硫解酶的晶体学和动力学研究：钾和氯离子对其结构和功能的重要性。

  摘要：

  硫醇酶是依赖于CoA的酶，可在Claisen缩合步骤中催化碳-碳键的形成及其通过硫解降解机理的逆反应。线粒体乙酰乙酰辅酶A（CoA）硫解酶（T2）在合成和降解酮体以及降解2-甲基乙酰乙酰辅酶A的途径中很重要。已在60多名患者中发现了人类T2缺乏症。T2的独特性质是它被钾离子激活。据报道，载脂蛋白形式和CoA络合物具有和不具有结合的钾离子，都具有高分辨率的人类T2晶体结构。钾离子结合在CoA结合位点和催化位点附近。钾离子在此低亲和力结合位点的结合导致CoA结合环和活性位点环的刚性化。出乎意料的是，还已经确定了氯离子的高亲和力结合位点。氯离子被共纯化，其结合位点位于二个催化环附近的二聚体界面。T2的独特属性是它可以使用2-甲基支链的乙酰乙酰基-CoA作为底物，而其他结构特征化的硫磺酶则不能利用2-甲基化的化合物。动力学测量表明，T 2可以以相似的催化效率降解乙酰乙酰辅酶A和2-甲基乙酰乙酰辅酶A。对于两种底物，当钾离子浓度从0

  DOI：

  10.1021/bi6026192

文献信息

• Unprecedented acetoacetyl-coenzyme A synthesizing enzyme of the thiolase superfamily involved in the mevalonate pathway
  作者：Eiji Okamura、Takeo Tomita、Ryuichi Sawa、Makoto Nishiyama、Tomohisa Kuzuyama

  DOI：10.1073/pnas.1000532107

  日期：2010.6.22

  Acetoacetyl-CoA is the precursor of 3-hydroxy-3-methylglutaryl (HMG)-CoA in the mevalonate pathway, which is essential for terpenoid backbone biosynthesis. Acetoacetyl-CoA is also the precursor of poly-β-hydroxybutyrate, a polymer belonging to the polyester class produced by microorganisms. The de novo synthesis of acetoacetyl-CoA is usually catalyzed by acetoacetyl-CoA thiolase via a thioester-dependent Claisen condensation reaction between two molecules of acetyl-CoA. Here, we report that nphT7 , found in the mevalonate pathway gene cluster from a soil-isolated Streptomyces sp. strain, encodes an unusual acetoacetyl-CoA synthesizing enzyme. The recombinant enzyme overexpressed in Escherichia coli catalyzes a single condensation of acetyl-CoA and malonyl-CoA to give acetoacetyl-CoA and CoA. Replacement of malonyl-CoA with malonyl-(acyl carrier protein) resulted in loss of the condensation activity. No acetoacetyl-CoA synthesizing activity was detected through the condensation of two molecules of acetyl-CoA. Based on these properties of NphT7, we propose to name this unusual enzyme of the thiolase superfamily acetoacetyl-CoA synthase. Coexpression of nphT7 with the HMG-CoA synthase gene and the HMG-CoA reductase gene in a heterologous host allowed 3.5-fold higher production of mevalonate than when only the HMG-CoA synthase and HMG-CoA reductase genes were expressed. This result suggests that nphT7 can be used to significantly increase the concentration of acetoacetyl-CoA in cells, eventually leading to the production of useful terpenoids and poly-β-hydroxybutyrate.

  乙酰乙酰辅酶A是甲烷基异戊二烯酸途径中3-羟基-3-甲基戊二酰辅酶A的前体，对于萜类骨架的生物合成至关重要。乙酰乙酰辅酶A也是由微生物产生的聚酯类中的聚β-羟基丁酸的前体。乙酰乙酰辅酶A的新生通常由乙酰辅酶A硫酰酶通过两个乙酰辅酶A分子之间的硫酯依赖的克莱森缩合反应催化。在这里，我们报告了土壤分离的链霉菌菌株mevalonate途径基因簇中发现的nphT7编码一种不寻常的乙酰乙酰辅酶A合成酶。在大肠杆菌中过表达的重组酶催化乙酰辅酶A和马来酰辅酶A的单一缩合反应，产生乙酰乙酰辅酶A和辅酶A。用马来酰-(酰载体蛋白)代替马来酰辅酶A导致缩合活性丧失。通过两个乙酰辅酶A分子的缩合未检测到乙酰乙酰辅酶A合成活性。基于NphT7的这些特性，我们建议将这种不寻常的硫酰酶超家族酶命名为乙酰乙酰辅酶A合成酶。在异源宿主中与HMG-CoA合成酶基因和HMG-CoA还原酶基因共表达nphT7，使mevalonate的产量比仅表达HMG-CoA合成酶和HMG-CoA还原酶基因时提高了3.5倍。这个结果表明，nphT7可以被用来显著增加细胞中乙酰乙酰辅酶A的浓度，最终导致有用的萜类化合物和聚β-羟基丁酸的产生。
• Characterization of an Acyl-CoA Thioesterase That Functions as a Major Regulator of Peroxisomal Lipid Metabolism
  作者：Mary C. Hunt、Karianne Solaas、B. Frode Kase、Stefan E.H. Alexson

  DOI：10.1074/jbc.m106458200

  日期：2002.1

  sequestration and to facilitate excretion of chain-shortened carboxylic acids, acyl-CoA thioesterases, which catalyze the hydrolysis of acyl-CoAs to the free acid and CoASH, may play important roles. Here we have cloned and characterized a peroxisomal acyl-CoA thioesterase from mouse, named PTE-2 (peroxisomal acyl-CoA thioesterase 2). PTE-2 is ubiquitously expressed and induced at mRNA level by treatment

  过氧化物酶体在极长链脂肪酸和长链脂肪酸，二羧酸脂肪酸，胆汁酸中间体，前列腺素，白三烯，血栓烷，pristanic酸和异种生物羧酸的β-氧化中起作用。这些脂质主要是作为羧酸排泄缩短链，或运输到线粒体进行进一步代谢。这些羧酸中的几种被缓慢氧化，因此可能螯合辅酶A（CoASH）。为防止CoASH螯合并促进链缩短的羧酸的排泄，可催化酰基CoA水解为游离酸和CoASH的酰基CoA硫酯酶可能起重要作用。在这里，我们从小鼠克隆并表征了过氧化物酶体酰基辅酶A硫酯酶，称为PTE-2（过氧化物酶体酰基辅酶A硫酯酶2）。通过用过氧化物酶体增殖物WY-14643处理和禁食，PTE-2在mRNA水平普遍表达和诱导。这些治疗方法所见的诱导作用取决于过氧化物酶体增殖物激活的受体α。重组PTE-2对酰基辅酶A表现出宽的链长特异性，从短链，中链到长链酰基辅酶A，以及其他底物，包括三羟基辅前列腺酸辅酶A，羟甲基戊二酰辅酶A和
• Requirement for the Enzymes Acetoacetyl Coenzyme A Synthetase and Poly-3-Hydroxybutyrate (PHB) Synthase for Growth of <i>Sinorhizobium meliloti</i> on PHB Cycle Intermediates
  作者：Guo-qin Cai、Brian T. Driscoll、Trevor C. Charles

  DOI：10.1128/jb.182.8.2113-2118.2000

  日期：2000.4.15

  We have identified two Sinorhizobium meliloti chromosomal loci affecting the poly-3-hydroxybutyrate degradation pathway. One locus was identified as the gene acsA , encoding acetoacetyl coenzyme A (acetoacetyl-CoA) synthetase. Analysis of the acsA nucleotide sequence revealed that this gene encodes a putative protein with a molecular weight of 72,000 that shows similarity to acetyl-CoA synthetase in other organisms. Acetyl-CoA synthetase activity was not affected in cell extracts of glucose-grown acsA ::Tn 5 mutants; instead, acetoacetyl-CoA synthetase activity was drastically reduced. These findings suggest that acetoacetyl-CoA synthetase, rather than CoA transferase, activates acetoacetate to acetoacetyl-CoA in the S. meliloti poly-3-hydroxybutyrate cycle. The second locus was identified as phbC , encoding poly-3-hydroxybutyrate synthase, and was found to be required for synthesis of poly-3-hydroxybutyrate deposits.

  摘要 我们发现了两种 瓜萎镰刀菌 染色体位点。其中一个基因座被鉴定为 acsA ，编码乙酰乙酰辅酶 A（乙酰乙酰-CoA）合成酶。对 acsA 核苷酸序列分析表明，该基因编码一种分子量为 72,000 的假定蛋白质，与其他生物的乙酰-CoA 合成酶相似。乙酰-CoA合成酶的活性在葡萄糖培养的 acsA ：：Tn 5 突变体的细胞提取物中，乙酰乙酰-CoA 合成酶的活性并未受到影响；相反，乙酰乙酰-CoA 合成酶的活性却急剧下降。这些研究结果表明，乙酰乙酰-CoA 合成酶，而不是 CoA 转移酶，能将乙酰乙酸活化为乙酰乙酰-CoA。 S. meliloti 多-3-羟基丁酸循环。第二个基因座被鉴定为 phbC 编码多-3-羟基丁酸合成酶，并发现它是合成多-3-羟基丁酸沉淀物所必需的。
• Characterization of a β-hydroxybutyryl-CoA dehydrogenase from Mycobacterium tuberculosis
  作者：Rebecca C. Taylor、Alistair K. Brown、Albel Singh、Apoorva Bhatt、Gurdyal S. Besra

  DOI：10.1099/mic.0.038802-0

  日期：2010.7.1

  The lipid-rich cell wall of mycobacteria is essential not only for virulence but also for survival. Whilst anabolic pathways for mycobacterial lipid biosynthesis have been well studied, there has been little research looking into lipid catabolism. The genome of Mycobacterium tuberculosis encodes multiple enzymes with putative roles in the β-oxidation of fatty acids. In this report we explore the functionality of FadB2, one of five M. tuberculosis homologues of a β-hydroxybutyryl-CoA dehydrogenase, an enzyme that catalyses the third step in the β-oxidation cycle. Purified M. tuberculosis FadB2 catalysed the in vitro NAD⁺-dependent dehydration of β-hydroxybutyryl-CoA to acetoacetyl-CoA at pH 10. Mutation of the active-site serine-122 residue resulted in loss of enzyme activity, consistent with the function of FadB2 as a fatty acyl dehydrogenase involved in the β-oxidation of fatty acids. Surprisingly, purified FadB2 also catalysed the reverse reaction, converting acetoacetyl-CoA to β-hydroxybutyryl-CoA, albeit in a lower pH range of 5.5–6.5. Additionally, a null mutant of fadB2 was generated in Mycobacterium smegmatis. However, the mutant showed no significant differences from the wild-type strain with regard to lipid composition, utilization of different fatty acid carbon sources and tolerance to various stresses; the absence of any phenotype in the mutant strain could be due to the potential redundancy between the five M. smegmatis fadB paralogues.

  分析表明，分解脂质是支持分枝杆菌生存和致病性的重要途径，但与脂质生物合成相比，关于脂质分解的研究较少。结核分枝杆菌基因组编码多种酶，可能在脂肪酸β-氧化中发挥作用。本研究探讨了FadB2的功能，它是五个M. tuberculosis同源物中的一个β-羟丁酰辅酶A脱氢酶，该酶催化β-氧化循环中的第三步。纯化的M. tuberculosis FadB2在pH10下催化了体外NAD+依赖的β-羟丁酰辅酶A的脱水反应，生成乙酰乙酰辅酶A。活性位点丝氨酸122的突变导致酶活性丧失，与FadB2作为脂肪酰脱氢酶参与脂肪酸β-氧化的功能一致。令人惊讶的是，纯化的FadB2也催化了反向反应，将乙酰乙酰辅酶A转化为β-羟丁酰辅酶A，但在较低的pH范围（5.5-6.5）内。此外，在Mycobacterium smegmatis中生成了fadB2的零突变体。然而，与野生型菌株相比，突变株在脂质组成、利用不同的脂肪酸碳源和耐受各种应激方面没有显著差异；突变株中没有任何表型可能是由于五个M. smegmatis fadB同源物之间的潜在冗余性。
• <i>Enterococcus faecalis</i> 3-Hydroxy-3-Methylglutaryl Coenzyme A Synthase, an Enzyme of Isopentenyl Diphosphate Biosynthesis
  作者：Autumn Sutherlin、Matija Hedl、Barbara Sanchez-Neri、John W. Burgner、Cynthia V. Stauffacher、Victor W. Rodwell

  DOI：10.1128/jb.184.15.4065-4070.2002

  日期：2002.8

  inhibitors for use as antibiotics. We used the PCR and Enterococcus faecalis genomic DNA to isolate the mvaS gene that encodes 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) synthase, the second enzyme of the mevalonate pathway. mvaS was expressed in Escherichia coli from a pET28 vector with an attached N-terminal histidine tag. The expressed enzyme was purified by affinity chromatography on Ni(2+)-agarose

  异戊二烯前体异戊烯基二磷酸酯（IPP）的生物合成通过两个不同的途径进行。序列比较和微生物学数据表明，革兰氏阳性球菌的多药耐药菌株仅利用甲羟戊酸途径进行IPP生物合成。因此，细菌甲羟戊酸途径酶为开发用作抗生素的活性定点抑制剂提供了潜在的靶标。我们使用PCR和粪肠球菌基因组DNA分离了编码3-羟-3-甲基戊二酰辅酶A（HMG-CoA）合酶（甲羟戊酸途径的第二种酶）的mvaS基因。mvaS在大肠杆菌中由带有附着的N端组氨酸标签的pET28载体表达。通过在Ni（2 +）-琼脂糖上进行亲和色谱纯化表达的酶，使其具有明显的均一性和10μmol/ min / mg的比活性。分析超离心表明该酶是二聚体（质量，83.9 kDa； s（20，w），5.3）。最佳活性发生在2.0 mM MgCl（2）中，温度为37（o）C。DeltaH（a）为6,000卡路里。pH活性曲线（在pH值为9.8时具有最佳活性）对于