午夜小网站 I 91热热热 I 少妇人妻挤奶水中文视频毛片 I 国精产品99永久一区一区 I 欧美黑人巨大videos极品 I 丰满老女人乱妇dvd在线播放 I 精品一区二区在线看 I 精品亚洲国产成人av I 在线va无卡无码高清 I 亚洲精品大全 I av天天射 I 国产无遮挡无码视频在线观看 I 少妇久久久久久久久久 I 久久精品亚洲精品 I 成人视屏在线 I 午夜色区 I 丁香七月激情 I 亚洲风情av I 97色爽 I 亚洲黄视频在线观看 I 在线播放免费人成毛片乱码 I 青草av久久一区二区三区 I 日本免费视频在线观看 I 久久伊人在 I 成人精品一区二区三区中文字幕 I 2018av天堂在线视频精品观看 I 日韩经典中文字幕 I 亚洲麻豆国产 I 欧洲国产精品无码专区影院 I 一级a毛片高清视频 I 碰超在线97人人 I 看欧美日韩国产 I 小泽玛丽亚在线观看 I 成人在线高清免费 I 精品国产网站

sigmaL-天冬酰胺

L-Asparagine monohydrate
Product Number A 8381
Store at Room Temperature
Product Description
Molecular Formula: C4H8N2O3 • H2O
Molecular Weight: 150.1
CAS Number: 5794-13-8
pKa: 2.14 （-COOH）, 8.72 （-NH2）1
pI: 5.431
Specific Rotation: +32.6°
（10 mg/ml, 0.1 M HCl, 20 °C）
Melting Point: 234-235 °C2
Synonyms: （S）-2-aminosuccinic acid 4-amide,
L-aspartic acid 4-amide, α-aminoauccinamic acid,
aspartic acid β-amide2
The amino acid L-asparagine is a structural analog of
L-aspartic acid, where the side chain of the carboxylic
acid moiety is amidated, to give a terminal amine
group. This renders L-asparagine neutral at
physiological pH. The amide group of asparagine is
derived from glutamate, in the reaction of aspartate
and glutamine in the presence of ATP to yield
asparagine and glutamate.3 In vivo, asparagine is
hydrolyzed to aspartate and NH4
+ by asparaginase.4
Asparagine is also an important amino acid in
glycopeptide bonds, via N-glycosyl linkages to the
sugar rings.3
L-Asparagine is used in cell culture media and is a
component of MEM non-essential amino acids solution
（Product No. M 7145）. L-Asparagine has been shown
to enhance ornithine decarboxylase activity in cultured
human colon adenocarcinoma Caco-2 cells and in
cultured IEC-6 intestinal epithelial cells.5,6 Spore
germination in Bacillus subtilis has been increased in
the presence of L-asparagine.7
An isoxazoline RGD mimic plaet GPIIb/IIIa
antagonist has been prepared by chiral synthesis with
L-asparagine as a starting material.8 L-Asparagine
has been utilized in the synthesis of 4-azalysine
building blocks for application to combinatorial
chemistry.9
Precautions and Disclaimer
For Laboratory Use Only. Not for drug, household or
other uses.
Preparation Instructions
This product is soluble in water （50 mg/ml）, with heat
as needed, yielding a clear, colorless solution.
References
1. Molecular Biology Lab, Brown, T. A., ed., BIOS
Scientific Publishers （Oxford, UK: 1991）, p. 29.
2. The Merck Index, 12th ed., Entry# 872.
3. Textbook of Biochemistry with Clinical
Correlations, 5th ed., Devlin, T. M., ed., Wiley-Liss
（New York, NY: 2002）, pp. 97, 680-681, 785-786.
4. Biochemistry, 3rd ed., Stryer, L., W. H. Freeman
（New York, NY: 1988）, pp. 18, 504.
5. Chabanon, H., et al., Increased translation
efficiency and antizyme-dependent stabilization of
ornithine decarboxylase in amino acidsupplemented
human colon adenocarcinoma
cells, Caco-2. Biochem. J., 348（Pt 2）, 401-408
（2000）.
6. Ray, R. M., et al., Interaction of asparagine and
EGF in the regulation of ornithine decarboxylase in
IEC-6 cells. Am. J. Physiol., 276（3 Pt 1）, G773-
780.
7. Cabrera-Martinez, R. M., et al., Effects of
overexpression of nutrient receptors on
germination of spores of Bacillus subtilis. J.
Bacteriol., 185（8）, 2457-2464 （2003）.
8. Zhang L. H., et al., The Enantiospecific synthesis
of an isoxazoline. A RGD mimic plaet GPIIb/IIIa
antagonist. J. Org. Chem., 62（8）, 2466-2470
（1997）.
9. Chhabra, S. R., et al., Homochiral 4-azalysine
building blocks: syntheses and applications in
solid-phase chemistry. J. Org. Chem., 67（12）,
4017-4029 （2002）.
GCY/RXR 8/03
Sigma brand

sigmaL-天冬酰胺 詳細產品信息可和選購