L-cysteinate | 41079-66-7

• 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: L-cysteinate
• 英文别名: cysteine anion；Cys anion；[Cys-H](-)；L-cysteine; deprotonated form；(2R)-2-amino-3-sulfanylpropanoate
• CAS: 41079-66-7
• 化学式: C₃H₆NO₂S
• 分子量: 120.152
• InChiKey: XUJNEKJLAYXESH-REOHCLBHSA-M

计算性质

• 辛醇/水分配系数(LogP)：
  -2.5
• 重原子数：
  7
• 可旋转键数：
  2
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.67
• 拓扑面积：
  64.3
• 氢给体数：
  2
• 氢受体数：
  4

ADMET

代谢

L-半胱氨酸是人体硫代谢中的中心化合物。在蛋白质中，半胱氨酸的巯基之间形成二硫键对于三级结构和酶活性起着重要作用；然而，半胱氨酸总是以半胱氨酸的形式被纳入多肽链中。L-半胱氨酸通过两个步骤降解为丙酮酸：一是去除硫，二是转氨作用。半胱氨酸可以通过半胱氨酸亚磺酸途径代谢形成牛磺酸和二氧化碳，其中的初始步骤是半胱氨酸氧化为半胱氨酸亚磺酸。这一步骤是由半胱氨酸双加氧酶催化的。半胱氨酸亚磺酸随后可能被脱羧形成牛磺酸，或者通过假设的中间体beta-亚磺基丙酮酸代谢为丙酮酸和亚硫酸盐，然后进一步转化为二氧化碳和硫酸盐。

L-Cysteine is the central compound in sulfur metabolism in the human body. In proteins the formation of disulfide bonds between the thiol groups of cysteine plays an important role for tertiary structure and enzymatic activity; cysteine is however always incorporated in the polypeptide chain as cysteine. L-Cysteine is degraded to pyruvate in two steps: one is removal of sulfur and the other is a transamination. Cysteine can be metabolized to form taurine and carbon dioxide through the cysteinsulfinate pathway, where the initial step is oxidation of cysteine to cysteine sulfinate. This step is catalyzed by cysteine dioxygenase. Cysteine sulfinate may then be decarboxylated to form taurine or it may be metabolized via the putative intermediate beta-sulfinylpyruvate to pyruvate and sulfite and then to carbon dioxide and sulfate.

来源:Hazardous Substances Data Bank (HSDB)

代谢

氨基酸分解对于调整游离氨基酸池的大小至关重要，并参与能量产生以及营养物质的再动员。碳骨架通常转化为三羧酸循环的前体或中间体。在半胱氨酸的情况下，来自巯基的还原硫也必须被氧化，以防止积累到有毒浓度。在这里，我们提出了一个线粒体硫分解途径，它催化L-半胱氨酸完全氧化为丙酮酸和硫代硫酸盐。经过转氨作用生成3-巯基丙酮酸后，L-半胱氨酸的巯基团通过硫转移酶1转移到谷胱甘肽，并经ETHE1的硫双氧酶氧化为亚硫酸盐。然后，亚硫酸盐通过硫转移酶1添加第二个过硫化物基团转化为硫代硫酸盐。该途径在早期胚胎发育和光照限制条件下的营养生长中最为相关。对拟南芥ETHE1和硫转移酶1的T-DNA插入线双突变体的表征表明，ETHE1依赖途径的一个中间体，很可能是过硫化物，干扰了氨基酸分解并诱导早期衰老。

Amino acid catabolism is essential for adjusting pool sizes of free amino acids and takes part in energy production as well as nutrient remobilization. The carbon skeletons are generally converted to precursors or intermediates of the tricarboxylic acid cycle. In the case of cysteine, the reduced sulfur derived from the thiol group also has to be oxidized in order to prevent accumulation to toxic concentrations. Here we present a mitochondrial sulfur catabolic pathway catalyzing the complete oxidation of L-cysteine to pyruvate and thiosulfate. After transamination to 3-mercaptopyruvate the sulfhydryl group from L-cysteine is transferred to glutathione by sulfurtransferase 1 and oxidized to sulfite by the sulfur dioxygenase ETHE1. Sulfite is then converted to thiosulfate by addition of a second persulfide group by sulfurtransferase 1. This pathway is most relevant during early embryo development and for vegetative growth under light limiting conditions. Characterization of a double mutant produced from Arabidopsis thaliana T-DNA insertion lines for ETHE1 and sulfurtransferase 1 revealed that an intermediate of the ETHE1 dependent pathway, most likely a persulfide, interferes with amino acid catabolism and induces early senescence.

来源:Hazardous Substances Data Bank (HSDB)

毒理性

• 毒性总结

识别和使用：半胱氨酸形成白色或无色晶体。它用于生化研究和营养研究，作为面包面团中的还原剂（高达90 ppm）。它还用作调味剂和药物，包括兽药。人类接触和毒性：半胱氨酸溶液（3%）对人类眼睛无刺激性。动物研究：单次向兔子眼睛应用L-半胱氨酸0.1克的剂量产生了轻微的刺激作用，这些作用在48小时内完全可逆。在三个兔子背部单次应用L-半胱氨酸0.5克的剂量，既无刺激作用也无腐蚀作用。在大剂量接受半胱氨酸的大鼠中观察到窝产仔数减少，这与排卵未受精卵和胚胎的退化和/或死亡以及透明带的变化有关，这些变化在卵巢中已经受到影响。在怀孕的最后一天，给小鼠和大鼠皮下注射1.2毫克/克，一天后观察到胎儿脑退化。在HPRT位点上，L-半胱氨酸被认为对中国仓鼠V79细胞不具有突变性。L-半胱氨酸没有在中国仓鼠V79细胞系中诱导结构染色体畸变。生态毒性研究：研究的目的是确定半胱氨酸对鲤鱼（Cyprinus carpio）解冻后精子活动力、精子活动持续时间、DNA损伤和繁殖能力的影响。补充半胱氨酸增加了受精率和孵化率，并减少了DNA损伤。

IDENTIFICATION AND USE: Cysteine forms white or colorless crystals. It is used in biochemical and nutrition research, as a reducing agent in bread doughs (up to 90 ppm). It is also used as flavor enhancer and medication, including veterinary medication. HUMAN EXPOSURE AND TOXICITY: Cysteine solution (3%) was not irritating for human eyes. ANIMAL STUDIES: A single ocular application of L-cysteine to rabbits at a dose of 0.1 g produced slight irritant effects, which were fully reversible within 48 hours. The single dermal application of L-cysteine to three rabbits at a dose of 0.5 g showed neither irritant nor corrosive effects. Decreased litter size observed in rats receiving high-dose cysteine, which was related to the degeneration and/or death of ovulated unfertilized oocytes and embryos with changes in the zona pellucida, which was already affected in the ovary. Pregnant mice and rats were treated s.c. with 1.2 mg per g on the last day of pregnancy and brain degeneration was observed one day later in the fetus. L-Cysteine is considered to be non-mutagenic in the HPRT locus using V79 cells of the Chinese Hamster. L-Cysteine did not induce structural chromosomal aberrations in the V79 Chinese hamster cell line. ECOTOXICITY STUDIES: The objective of the study was to determine the effects of cysteine on postthaw sperm motility, duration of sperm motility, DNA damage, and fertility in the common carp (Cyprinus carpio). Supplementation with cysteine increased the fertilization and hatching rate and decreased DNA damage.

来源:Hazardous Substances Data Bank (HSDB)

毒理性

• 解毒与急救

/SRP:/ 立即急救：确保已经进行了充分的中和。如果患者停止呼吸，请开始人工呼吸，最好使用需求阀复苏器、球囊阀面罩设备或口袋面罩，按训练操作。如有必要，执行心肺复苏。立即用缓慢流动的水冲洗受污染的眼睛。不要催吐。如果患者呕吐，让患者向前倾或将其置于左侧（如果可能的话，头部向下），以保持呼吸道畅通，防止吸入。保持患者安静，维持正常体温。寻求医疗帮助。 /毒物A和B/

/SRP:/ Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR if necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on the left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Poisons A and B/

来源:Hazardous Substances Data Bank (HSDB)

毒理性

• 解毒与急救

/SRP:/ 基本治疗：建立专利气道（如有需要，使用口咽或鼻咽气道）。如有必要，进行吸痰。观察呼吸不足的迹象，如有需要，协助通气。通过非循环呼吸面罩以10至15升/分钟的速度给予氧气。监测肺水肿，如有必要，进行治疗……。监测休克，如有必要，进行治疗……。预期癫痫发作，如有必要，进行治疗……。对于眼睛污染，立即用水冲洗眼睛。在运输过程中，用0.9%的生理盐水（NS）持续冲洗每只眼睛……。不要使用催吐剂。对于摄入，如果患者能够吞咽、有强烈的干呕反射且不流口水，则用温水冲洗口腔，并给予5毫升/千克，最多200毫升的水进行稀释……。在去污后，用干燥的无菌敷料覆盖皮肤烧伤……。/毒药A和B/

/SRP:/ Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if needed. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock and treat if necessary ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 mL/kg up to 200 mL of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool ... . Cover skin burns with dry sterile dressings after decontamination ... . /Poisons A and B/

来源:Hazardous Substances Data Bank (HSDB)

毒理性

• 解毒与急救

/SRP:/ 高级治疗：对于昏迷、严重肺水肿或严重呼吸困难的病人，考虑进行口咽或鼻咽气管插管以控制气道。使用气囊面罩装置的正压通气技术可能有益。考虑使用药物治疗肺水肿……。对于严重的支气管痉挛，考虑给予β激动剂，如沙丁胺醇……。监测心率和必要时治疗心律失常……。开始静脉输注D5W TKO /SRP: "保持开放"，最低流量/。如果出现低血容量的迹象，使用0.9%生理盐水（NS）或乳酸钠林格氏液（LR）。对于伴有低血容量迹象的低血压，谨慎给予液体。注意液体过载的迹象……。用地西泮或劳拉西泮治疗癫痫……。使用丙美卡因氢氯化物协助眼部冲洗……。/毒物A和B/

/SRP:/ Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Positive-pressure ventilation techniques with a bag valve mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Consider administering a beta agonist such as albuterol for severe bronchospasm ... . Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start IV administration of D5W TKO /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's (LR) if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload ... . Treat seizures with diazepam or lorazepam ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Poisons A and B/

来源:Hazardous Substances Data Bank (HSDB)

毒理性

• 人类毒性摘录

人类暴露研究/ ... 以3%的中性溶液应用于 ... 人类眼睛 ... 没有报告不良反应。

/HUMAN EXPOSURE STUDIES/ ... Applied as a 3% near-neutral soln to ... human eyes ... no adverse effect is reported.

来源:Hazardous Substances Data Bank (HSDB)

反应信息

• 作为反应物：
  描述：

  L-cysteinate 在 三氟乙基醇-OD 作用下， 生成
  参考文献：
  名称：

  气相中去质子化氨基酸和肽的氢-氘交换和选择性标记

  摘要：

  研究了去质子化氨基酸和小肽的氢-氘交换反应。可以在赖氨酸的 α-氨基（4 个不稳定氢中的 2 个与 CF3CH2OD 交换）和精氨酸的胍侧链（6 个不稳定氢中的 3 个与 CH3CH2OD 和 C6H5CH2OD 交换）进行选择性标记。还完成了肽的差异标记，H/D 交换的程度取决于存在的氨基酸以及它们在链中的顺序。

  DOI：

  10.1021/ja076599l
• 作为产物：
  描述：

  L-胱氨酸 以 水 为溶剂， 生成 Cysteine thiyl radical 、 L-cysteinate
  参考文献：
  名称：

  Kinetics of One-Electron Oxidation of Thiols and Hydrogen Abstraction by Thiyl Radicals from .alpha.-Amino C-H Bonds

  摘要：

  One-electron oxidation of cysteine, homocysteine, and glutathione by azide radical in alkaline solution (pH 10.5), where both the amino and the SH groups are deprotonated, has been investigated by pulse radiolysis. Reducing alpha-aminoalkyl radicals ((.)CR), which are formed via intramolecular rearrangement of thiyl radicals, were detected using methylviologen as oxidant in the kinetic analysis. The general scheme of the reactions is sketched. Thiyl radicals either equilibrate with RSSR(.-) in reaction 5, RS(.) + RS(-) = RSSR(.-), or undergo intramolecular transformation via equilibrium 6, RS(.) = (.)CR. At pH 10.5, equilibrium 6 is completely shifted to the right, resulting in alpha-aminoalkyl radical formation. The rate constants in the reaction scheme for cysteine, homocysteine, and glutathione were measured. With the rate constants obtained, the decay kinetics of RSSR(.-) into (.)CR was simulated, and it agreed with that measured at 420 nm. At pH 10.5, the first-order rate constants for the transformation (k(6)) were determined to be 2.5 x 10(4), 1.8 x 10(5) and 2.2 x 10(5) s(-1) for cysteine, homocysteine, and glutathione, respectively. The rate constants for intermolecular hydrogen abstraction by thiyl radicals from alpha-amino C-H bonds of alanine and glycine were determined at the same pH to be 7.7 x 10(5) and 3.2 x 10(5) M(-1) s(-1), respectively. Thermodynamic estimation places the reduction potential E degrees(H2NC(CO2-)CH3)(.), H+/H2NCH(CO2-)CH3) at ca. 1.22 V, which implies a rather weak tertiary C-H bond in the anion of alpha-amino acids. Thus, an intramolecular hydrogen abstraction mechanism for the transformation of thiyl radical to alpha-amino carbon-centered radical is postulated. Molecular geometry plays an important part in deciding the transformation rates (k(6)) of different thiyl radicals.

  DOI：

  10.1021/ja00105a048

文献信息

• A multinuclear (1H, 13C, 113Cd) nuclear magnetic resonance and magnetic circular dichroism spectroscopic study of thiolate complexes of cadmium
  作者：Geetha K. Carson、Philip A.W. Dean、Martin J. Stillman

  DOI：10.1016/s0020-1693(00)88548-5

  日期：1981.1

  chemical shifts are given for the complexes formed by 31 different thiolates individually in water at ambient probe temperature, and slow-exchange 1H and/or 13C and/or 113Cd NMR spectra are reported for several typical complexes at reduced temperature in CD3OD. In aqueous solution at ambient probe temperature, ligands with vicinal thiolate groups and −SCH2CHRS− (R = H, Me, Et, CH2OH, CH2SO−3 or CH2S−)) form

  1H，13C和113Cd NMR的适当组合已用于研究ca。在过量的硫醇盐存在下，由相应的难溶性硫氰酸镉形成的0.05M溶液中，富含113Cd的大量硫氰酸镧盐酸盐。此外，已记录了MCD光谱的稀度。10-5M，一组代表性的硫醇盐络合物的溶液。对于在环境探针温度下由31种不同的硫醇盐在水中分别形成的配合物，给出了镉113的化学位移，并且在CD3OD中报道了几种典型的配合物在降低的温度下的慢速交换1H和/或13C和/或113Cd NMR光谱。在环境探针温度下的水溶液中，具有邻位硫醇盐基团和-SCH2CHRS-（R = H，Me，Et，CH2OH，CH2SO-3或CH2S-）的配体形成具有δCd⪖778 ppm的双（螯合物）络合物，镉的局部微观对称性接近四面体。具体而言，在[Cd（SR）2.5] 0.5n-n（R = Me，Et或Pr）络合物在250 nm区域的S→Cd电荷转移带下表现出良好分辨的对称A项。二硫醇盐-S（CH2nS-（n
• Direct rate constant measurement of radical disulphide anion formation for cysteine and cysteamine in aqueous solution
  作者：Stephen P. Mezyk

  DOI：10.1016/0009-2614(95)00100-i

  日期：1995.3

  pulse radiolysis, laser photolysis and absorption spectroscopy have been used to directly determine rate constants for radical disulphide anion formation for cysteine and cysteamine in aqueous solution. The measured values for cysteine, over the pH range 7–12, allowed calculation of individual rate constants for the constituent reactions RS. + RSH → RSSR−. + H+ and RS. + RS− → RSSR−. as (3.39 ± 0.31)

  脉冲辐射分解，激光光解和吸收光谱技术已被直接用于确定水溶液中半胱氨酸和半胱胺的自由基二硫化物阴离子形成的速率常数。在7-12的pH范围内，半胱氨酸的测量值可以计算出组成反应RS的各个速率常数。+ RSH→RSSR −。+ H +和RS 。+ RS - →RSSR - 。如（3.39±0.31）×10 8和（1.21±0.04）×10 9 dm 3 mol -1 s -1， 分别。对于半胱胺类似值也通过该技术确定为（3.06±0.16）×10 8和（3.65±0.07）×10 9分米3摩尔-1小号-1。
• Differences in heterocycle basicity distinguish homocysteine from cysteine using aldehyde-bearing fluorophores
  作者：Aabha Barve、Mark Lowry、Jorge O. Escobedo、Katherine T. Huynh、Lovemore Hakuna、Robert M. Strongin

  DOI：10.1039/c4cc03527e

  日期：——

  Homocysteine reacts with aldehyde-derived fluorescein to form thiazinane. Controlled protonation of the thiazinane amine leads to fluorescence enhancement, thus distinguishing homocysteine from cysteine.

  同型半胱氨酸与醛衍生的荧光素反应形成噻嗪环。对噻嗪环胺的控制质子化导致荧光增强，从而区分同型半胱氨酸和半胱氨酸。
• Nitric Oxide and Nitroxyl Products from the Reaction of <scp>L</scp> ‐Cysteine with <i>trans</i> ‐[RuNO(NH ₃ ) ₄ P(OEt) ₃ ](PF ₆ ) ₃
  作者：José Clayston Melo Pereira、Maykon Lima Souza、Douglas Wagner Franco

  DOI：10.1002/ejic.201402992

  日期：2015.2

  The reaction between the trans-[RuNO(NH3)4P(OEt)3](PF6)3 and L-cysteine (RS–) was studied over a pH range of 2.0–7.4. In this reaction, the concentrations of NO and HNO produced varied as a function of the pH of the solution. The first step of this reaction proceeded quickly [k1 = (3.5 ± 0.3) × 103 M–1 s–1, pH = 3.5, 25 °C] and resulted in the formation of trans-[Ru(NH3)4P(OEt)3N(O)SR]2+, which dissociated

  反式-[RuNO(NH3)4P(OEt)3](PF6)3 和 L-半胱氨酸 (RS-) 之间的反应在 2.0-7.4 的 pH 范围内进行了研究。在该反应中，产生的 NO 和 HNO 的浓度随溶液的 pH 值而变化。该反应的第一步进行得很快 [k1 = (3.5 ± 0.3) × 103 M–1 s–1, pH = 3.5, 25 °C] 并导致形成反式 [Ru(NH3)4P(OEt) 3N(O)SR]2+，其解离产生反式-[Ru(NH3)4P(OEt)3NO·]2+和RS·。然而，反式-[Ru(NH3)4P(OEt)3N(O)SR]n–1 可以与第二个 L-半胱氨酸反应，产生反式-[Ru(NH3)4P(OEt)3N(O)(SR) 2]+ [k2 = (3.6 ± 0.1) M–1 s–1, pH = 3.5, 25 °C]。因此，反式-[Ru(NH3)4P(OEt)3NO·]2+物种释放
• Kinetics of One-Electron Oxidation of Thiols and Hydrogen Abstraction by Thiyl Radicals from .alpha.-Amino C-H Bonds
  作者：Rong Zhao、Johan Lind、Gabor Merenyi、Trygve E. Eriksen

  DOI：10.1021/ja00105a048

  日期：1994.12

  One-electron oxidation of cysteine, homocysteine, and glutathione by azide radical in alkaline solution (pH 10.5), where both the amino and the SH groups are deprotonated, has been investigated by pulse radiolysis. Reducing alpha-aminoalkyl radicals ((.)CR), which are formed via intramolecular rearrangement of thiyl radicals, were detected using methylviologen as oxidant in the kinetic analysis. The general scheme of the reactions is sketched. Thiyl radicals either equilibrate with RSSR(.-) in reaction 5, RS(.) + RS(-) = RSSR(.-), or undergo intramolecular transformation via equilibrium 6, RS(.) = (.)CR. At pH 10.5, equilibrium 6 is completely shifted to the right, resulting in alpha-aminoalkyl radical formation. The rate constants in the reaction scheme for cysteine, homocysteine, and glutathione were measured. With the rate constants obtained, the decay kinetics of RSSR(.-) into (.)CR was simulated, and it agreed with that measured at 420 nm. At pH 10.5, the first-order rate constants for the transformation (k(6)) were determined to be 2.5 x 10(4), 1.8 x 10(5) and 2.2 x 10(5) s(-1) for cysteine, homocysteine, and glutathione, respectively. The rate constants for intermolecular hydrogen abstraction by thiyl radicals from alpha-amino C-H bonds of alanine and glycine were determined at the same pH to be 7.7 x 10(5) and 3.2 x 10(5) M(-1) s(-1), respectively. Thermodynamic estimation places the reduction potential E degrees(H2NC(CO2-)CH3)(.), H+/H2NCH(CO2-)CH3) at ca. 1.22 V, which implies a rather weak tertiary C-H bond in the anion of alpha-amino acids. Thus, an intramolecular hydrogen abstraction mechanism for the transformation of thiyl radical to alpha-amino carbon-centered radical is postulated. Molecular geometry plays an important part in deciding the transformation rates (k(6)) of different thiyl radicals.