L-selenomethionine Se-oxide | 19192-78-0

• 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-selenomethionine Se-oxide
• 英文别名: selenomethionine selenoxide；L-methionine selenoxide；SeOMet；(2S)-2-amino-4-methylseleninylbutanoic acid
• CAS: 19192-78-0
• 化学式: C₅H₁₁NO₃Se
• 分子量: 212.107
• InChiKey: KGXZPWNBFWCDRF-YGVKFDHGSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  -0.16
• 重原子数：
  10
• 可旋转键数：
  4
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.8
• 拓扑面积：
  80.4
• 氢给体数：
  2
• 氢受体数：
  4

反应信息

• 作为产物：
  描述：

  L-硒代蛋氨酸 在 双氧水 作用下， 反应 0.25h， 以85%的产率得到L-selenomethionine Se-oxide
  参考文献：
  名称：

  Oxidative Metabolism of Seleno-l-methionine to l-Methionine Selenoxide by Flavin-Containing Monooxygenases

  摘要：

  The roles of flavin-containing monooxygenases (FMOs) in the oxidation of seleno-L-methionine (SeMet) to L-methionine selenoxide (MetSeO) were investigated using cDNA-expressed human FMOs, purified rat liver FMOs, and rat liver microsomes. MetSeO and the N-2,4-dinitrophenyl-derivatives of SeMet and MetSeO were synthesized and characterized by 1H-NMR and ESI/MS. These reference compounds were then used to develop a sensitive HPLC assay to monitor SeMet oxidation to MetSeO. The formation of MetSeO in rat liver microsomes was time-, protein concentration-, SeMet concentration-, and NADPH- dependent. The microsomal activity exhibited a SeMet K-m value (mean +/- S.D.; n = 4) of 0.91 +/- 0.29 mM and a V-max value of 44 +/- 8.0 nmol MetSeO/mg protein/min. The inclusion of 1-benzylimidazole, superoxide dismutase, or deferoxamine caused no inhibition of the rat liver microsomal activity. Because these results suggested the involvement of FMOs in the oxidation of SeMet in rat liver microsomes, the formation of MetSeO was also examined using cDNA-expressed human and purified rat FMOs. The results showed that both rat and human FMO1 and FMO3 but not FMO5 can catalyze the reaction. The SeMet kinetic constants were obtained with purified rat liver FMO3 (K-m = 0. 11 mM, V-max = 280 nmol/ mg protein/min) and rat liver FMO1 (K-m = 7.8 mM, V-max = 1200 nmol/mg protein/min). Because SeMet has anti-cancer, chemopreventive, and toxic properties, the kinetic results suggest that FMO3 is likely to play a role in the biological activities of SeMet at low exposure conditions.

  DOI：

  10.1021/tx0601915

文献信息

• Selenium Speciation and Bioavailability in Biofortified Products Using Species-Unspecific Isotope Dilution and Reverse Phase Ion Pairing−Inductively Coupled Plasma−Mass Spectrometry
  作者：J. K. Kirby、G. H. Lyons、M. P. Karkkainen

  DOI：10.1021/jf073030v

  日期：2008.3.1

  In some regions of the world, where the bioavailability of selenium (Se) in soil is low and/or declining (e.g., due to use of high-sulfur fertilizers), there is increased risk of adverse affects on animals and human health. In recent years, increased research attention has focused on understanding the relationships between Se contents in foods and supplements and their nutritional benefits for animal and humans. The objective of this study was to use a species-unspecific isotope dilution and reverse phase ion pairing-inductively coupled plasma-mass spectrometry techniques for the identification and quantification of Se species in biofortified grains (i.e., wheat and triticale), flour, and wheat biscuits. The information on Se species was used to gain an understanding of the bioavailability of Se in biofortified and process-fortified wheat biscuits used in a clinical trail. The major Se species identified in biofortified and process-fortified samples were selenomethionine (76-85%) and selenomethionine, selenoxide (51-60%), respectively. Total plasma Se concentrations in the biofortified Se exposure group were found to increase throughout the 6 month trial period (mean = 122 mu g L-1 at 0 months to 194 mu g L-1 at 6 months). In contrast, the trial group exposed to process-fortified Se biscuits showed little increase in mean total Se plasma concentrations until 4 months of exposure (mean = 122 mu g L-1 at 0 months to 140 mu g L-1 at 4 months) that remained constant until the end of the trial period (mean = 140 mu g L-1 at 4 months to 138 mu g L-1 at 6 months). The difference in total Se plasma concentrations may be due to the presence and bioavailability of different Se species in biofortified and process-fortified biscuits. An understanding of Se speciation in foods enables better understanding of pathways and their potential benefits for animals and humans.
• Oxidative Metabolism of Seleno-<scp>l</scp>-methionine to <scp>l</scp>-Methionine Selenoxide by Flavin-Containing Monooxygenases
  作者：Renee J. Krause、Steven C. Glocke、Anna Rita Sicuri、Sharon L. Ripp、Adnan A. Elfarra

  DOI：10.1021/tx0601915

  日期：2006.12.1

  The roles of flavin-containing monooxygenases (FMOs) in the oxidation of seleno-L-methionine (SeMet) to L-methionine selenoxide (MetSeO) were investigated using cDNA-expressed human FMOs, purified rat liver FMOs, and rat liver microsomes. MetSeO and the N-2,4-dinitrophenyl-derivatives of SeMet and MetSeO were synthesized and characterized by 1H-NMR and ESI/MS. These reference compounds were then used to develop a sensitive HPLC assay to monitor SeMet oxidation to MetSeO. The formation of MetSeO in rat liver microsomes was time-, protein concentration-, SeMet concentration-, and NADPH- dependent. The microsomal activity exhibited a SeMet K-m value (mean +/- S.D.; n = 4) of 0.91 +/- 0.29 mM and a V-max value of 44 +/- 8.0 nmol MetSeO/mg protein/min. The inclusion of 1-benzylimidazole, superoxide dismutase, or deferoxamine caused no inhibition of the rat liver microsomal activity. Because these results suggested the involvement of FMOs in the oxidation of SeMet in rat liver microsomes, the formation of MetSeO was also examined using cDNA-expressed human and purified rat FMOs. The results showed that both rat and human FMO1 and FMO3 but not FMO5 can catalyze the reaction. The SeMet kinetic constants were obtained with purified rat liver FMO3 (K-m = 0. 11 mM, V-max = 280 nmol/ mg protein/min) and rat liver FMO1 (K-m = 7.8 mM, V-max = 1200 nmol/mg protein/min). Because SeMet has anti-cancer, chemopreventive, and toxic properties, the kinetic results suggest that FMO3 is likely to play a role in the biological activities of SeMet at low exposure conditions.