ASHLGLAR

• 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: ASHLGLAR
• 英文别名: Ala-Ser-His-Leu-Gly-Leu-Ala-Arg；(2S)-2-[[(2S)-2-[[(2S)-2-[[2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-aminopropanoyl]amino]-3-hydroxypropanoyl]amino]-3-(1H-imidazol-5-yl)propanoyl]amino]-4-methylpentanoyl]amino]acetyl]amino]-4-methylpentanoyl]amino]propanoyl]amino]-5-(diaminomethylideneamino)pentanoic acid
• 化学式: C₃₅H₆₁N₁₃O₁₀
• 分子量: 823.95
• InChiKey: LYTNSBOBASKUDN-GUQPKPMOSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  -5
• 重原子数：
  58
• 可旋转键数：
  26
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.66
• 拓扑面积：
  380
• 氢给体数：
  13
• 氢受体数：
  13

反应信息

• 作为反应物：
  描述：

  溴代乙酸酐 、 ASHLGLAR 以 乙腈 为溶剂， 反应 0.17h， 生成
  参考文献：
  名称：

  Matrix-assisted laser desorption/ionization mass spectrometry peptide sequencing utilizing selective N-terminal bromoacetylation

  摘要：

  In tandem mass spectrometric peptide sequencing, simplifying the mass spectrum is often desirable. The b-series ions were distinguished from the y-series ions in the MALDI TOF-TOF spectra by incorporating a bromine-tag to the N-terminal amino group through rapid and selective acetylation using bromoacetic anhydride without blocking the lysine and tyrosine residues. The 51:49 ratio of Br-79 and Br-81 isotopes facilitated identification of ions carrying the tag. With the Br-tag in the b-series ions, N-terminal sequencing of tryptic peptides from hemoglobin as well as model peptides was straightforward. When the b-ions were low in intensity, ions without the Br-tag were identified as y-ions and used for sequencing. (C) 2011 Elsevier Inc. All rights reserved.

  DOI：

  10.1016/j.ab.2011.11.022
• 作为试剂：
  描述：

  、 AYEMWCFHQK 在 ASHLGLAR 、 substance P(1-7) fragment 作用下， 以 四氢呋喃 、 水 为溶剂， 反应 24.0h， 生成
  参考文献：
  名称：

  缺乏电子的炔烃作为可裂解试剂，用于修饰水性介质中含半胱氨酸的肽

  摘要：

  富集的裂解：通过在水性介质中使用缺电子的炔烃，可以对未保护的肽和蛋白质进行有效的化学选择性半胱氨酸修饰。有趣的是，可以通过在温和条件下添加硫醇进行裂解，将末端炔酮修饰的肽转换回未修饰的肽（参见方案）。

  DOI：

  10.1002/chem.200800669

文献信息

• Simplifying Fragmentation Patterns of Multiply Charged Peptides by N-Terminal Derivatization and Electron Transfer Collision Activated Dissociation
  作者：James A. Madsen、Jennifer S. Brodbelt

  DOI：10.1021/ac9000942

  日期：2009.5.1

  N-terminal peptide derivatization strategies used in conjunction with tandem mass spectrometry to yield simplified fragmentation patterns have shown limited success for the de novo sequencing of multiply charged peptides, including those predominantly formed in LC−ESI-MS experiments. Significant proton mobilization occurs for multiply charged peptides upon collisional activation, resulting in the formation of both N-terminal and C-terminal product ions rather than an exclusive series of C-terminal ions preferred for de novo sequencing algorithms. To circumvent this problem, multiply charged, N-terminally derivatized peptides were subjected to electron transfer reactions with fluoranthene anions to produce singly charged, radical species. Upon subsequent “soft” collision induced dissociation (CID), highly abundant z-type ions were formed nearly exclusively, which yielded simplified fragmentation patterns amenable to de novo sequencing methods. Furthermore, the derivatized peptides retained labile phosphoric acid moieties, and the enhanced set of z ions were also observed for peptides not possessing basic C-terminal residues, a type of peptide that poses more challenges to traditional simplification methods based on collision activated dissociation. This improved LC−MSn strategy was demonstrated for a variety of multiply charged model peptides and a tryptic digest of myoglobin.

  在对多电荷肽（包括主要在 LC-ESI-MS 实验中形成的多电荷肽）进行从头测序时，N 端肽衍生策略与串联质谱法结合使用以产生简化的碎片模式，但效果有限。多电荷肽在碰撞活化过程中会发生大量质子移动，从而形成 N 端和 C 端产物离子，而不是从头测序算法所喜欢的一系列 C 端离子。为了解决这个问题，多电荷 N 端衍生肽与荧蒽阴离子发生电子转移反应，产生单电荷自由基物种。在随后的 "软 "碰撞诱导解离（CID）过程中，几乎只形成了高含量的z型离子，从而产生了适合全新测序方法的简化碎片模式。此外，衍生化的多肽保留了可迁移的磷酸分子，而且对于不具有基本 C 端残基的多肽也观察到了增强的 z 离子集，这种类型的多肽对基于碰撞激活解离的传统简化方法构成了更大的挑战。这种改进的 LC-MSn 策略在多种多电荷模型肽和肌红蛋白胰蛋白酶消化物中得到了验证。
• [EN] COMPOUND FOR DERIVATIZING POLYPEPTIDES AND METHOD FOR SEQUENCING AND QUANTIFIFYING AMINO ACIDS IN POLYPEPTIDES USING THE SAME<br/>[FR] COMPOSE PERMETTANT DE DERIVER DES POLYPEPTIDES, ET PROCEDE DE SEQUENÇAGE ET DE QUANTIFICATION D'ACIDES AMINES DANS DES POLYPEPTIDES FAISANT APPEL AUDIT COMPOSE
  申请人：UNIV KOREA IND & ACAD COOP

  公开号：WO2006004341A1

  公开（公告）日：2006-01-12

  The present invention relates to a compound for N-terminal substitution of polypeptides which is used in sequencing and quantifying amino acids and a method for sequencing and quantifying an amino acid sequence using the same. The method for sequencing and quantifying amino acids in accordance with the present invention leads to a relative quantitative analysis of proteins with very high reliability, and can distinctively discriminate between y-type ions and b-type ions on the MS/MS spectra, providing the means for realization of high-reliability protein identification.

  本发明涉及一种用于多肽N-末端替换的化合物，用于测序和定量氨基酸以及使用该化合物进行氨基酸序列测序和定量的方法。根据本发明的氨基酸测序和定量方法可以实现非常高可靠性的蛋白质相对定量分析，并且可以在MS / MS光谱上明显区分y型离子和b型离子，为实现高可靠性的蛋白质鉴定提供了手段。
• Peptide C-terminal Sequence Analysis by MALDI-TOF MS Utilizing EDC Coupling with Br Signature
  作者：Man-Sup Shin、Hie-Joon Kim

  DOI：10.5012/bkcs.2011.32.4.1183

  日期：2011.4.20

  The unique Br signature was utilized for C-terminal amino acid sequencing of model peptides. C-terminal carboxyl group was selectively derivatized in peptides, containing side chain carboxyl group, using 1-ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride (EDC) and Br was introduced using 4-bromophenylhydrazine hydrochloride (BPH) in a one pot reaction. Matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) tandem mass spectra were obtained carrying the Br signature in the y-series ions. The Br signature facilitated C-terminal sequencing and discrimination of C-terminal carboxyl groups in the free acid and amide forms.

  独特的溴标记被用于模型肽的C端氨基酸测序。在含有侧链羧基的肽中，使用1-乙基-3-[3-二甲基氨基丙基]碳二亚胺盐酸盐（EDC）选择性衍生C端羧基，并使用4-溴苯肼盐酸盐（BPH）在一锅反应中引入溴标记。在y系列离子中，矩阵辅助激光解吸/电离（MALDI）飞行时间（TOF）串联质谱获得了溴标记。溴标记有助于游离酸和酰胺形式的C端羧基的C端测序和区分。
• Improving de Novo Sequencing of Peptides Using a Charged Tag and C-Terminal Digestion
  作者：Weibin Chen、Peter J. Lee、Henry Shion、Nicholas Ellor、John C. Gebler

  DOI：10.1021/ac061670b

  日期：2007.2.1

  An improved method for peptide de novo sequencing by MALDI mass spectrometry is presented. The method couples a charge derivatization reaction with C-terminal digestion to modify tryptic peptides. The charge derivatization attaches a fixed charge group onto the N-termini of peptides, and the enzymatic digestion after the derivatization step removes C-terminal basic amino acid residues such as arginine and lysine. The fragmentation of the modified peptide(s) under low-energy CID conditions (MALDI Q-TOF mass spectrometer) yields a simplified yet complete ion series of the peptide sequence. The validity of the method is demonstrated by the results from several model protein digests, where peptide sequences were correctly deduced either manually or through an automated sequencing program.

  本文介绍了一种通过 MALDI 质谱进行肽从头测序的改进方法。该方法将电荷衍生反应与 C 端消化结合起来，对胰蛋白酶肽进行修饰。电荷衍生将一个固定的电荷基团附着在肽的 N 端，衍生步骤后的酶解去除 C 端基本氨基酸残基，如精氨酸和赖氨酸。在低能 CID 条件下（MALDI Q-TOF 质谱仪）对修饰肽进行碎裂，可得到简化但完整的肽序列离子系列。几种蛋白质消化模型的结果证明了该方法的有效性，无论是手动还是通过自动测序程序，都能正确推断出肽序列。
• Ultraviolet Photodissociation of Carboxylate-Derivatized Peptides in a Quadrupole Ion Trap
  作者：Byoung Joon Ko、Jennifer S. Brodbelt

  DOI：10.1007/s13361-010-0016-5

  日期：2011.1.1

  The fragmentation patterns obtained by ultraviolet photodissociation (UVPD) and collision-induced dissociation (CID) in a quadrupole ion trap mass spectrometer were compared for peptides modified at their C-termini and at acidic amino acids. Attachment of Alexa Fluor 350 or 7-amino-4-methyl-coumarin chromophores at the C-terminal and acidic residues enhances the UV absorptivity of the peptides and all fragment ions that retain the chromophore, such as the y ions that contain the chromophore-modified C-terminus. Whereas CID results in the formation of the typical array of mainly y-type and a/b-type fragment ions, UVPD produces predominantly a/b-type ions with greatly reduced abundances of y ions. Immonium ions, mostly ones from aromatic or basic amino acids, are also observed in the low m/z range upon UVPD. UVPD of peptides containing two chromophore moieties (with one at the C-terminus and another at an acidic residue) results in even more efficient photodissociation at the expense of the annihilation of almost all diagnostic b and y ions containing the chromophore.

  在四极离子阱质谱仪中，通过紫外线光解离（UVPD）和碰撞诱导解离（CID）获得的碎片模式，与在C端和酸性氨基酸处被修饰的肽进行了比较。在C端和酸性残基上附着Alexa Fluor 350或7-氨基-4-甲基-香豆素发色团，可增强肽和所有保留发色团的碎片离子的紫外线吸收性，例如包含发色团修饰的C端的y离子。CID会导致形成典型的y型和a/b型碎片离子阵列，而UVPD则主要产生a/b型离子，y离子的丰度大大降低。在UVPD作用下，在低m/z范围内也观察到了铵离子，其中大部分来自芳香族或碱性氨基酸。对于含有两个发色团（一个位于C端，另一个位于酸性残基）的肽，UVPD会导致更有效的光解离，但代价是几乎所有包含发色团的诊断性b和y离子都会消失。