英语翻译The protein is approximately 10000 timessweeter than sugar on a molar basis [28].It is a proteinthat tastes intensely sweet only to Old World monkeysand to higher primates,including man [29],as it has beenfound that the protein binds to c
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英语翻译The protein is approximately 10000 timessweeter than sugar on a molar basis [28].It is a proteinthat tastes intensely sweet only to Old World monkeysand to higher primates,including man [29],as it has beenfound that the protein binds to c
英语翻译
The protein is approximately 10000 times
sweeter than sugar on a molar basis [28].It is a protein
that tastes intensely sweet only to Old World monkeys
and to higher primates,including man [29],as it has been
found that the protein binds to certain elements in taste
pores of Rhesus monkey foliate papillae [30].Thaumatin
has been approved for use in many countries as both a flavor
enhancer and a high-intensity sweetener [31].
Monellin
Monellin,a sweet protein,consists of two noncovalently
associated polypeptide chains,an A chain of 44 amino
acid residues and a B chain of 50 amino acid residues [32].
The protein can be purified from the fruit of Dioscoreophyllum
cumminsii grown in West Africa and is approximately
100,000 times sweeter than sugar on a molar basis and
several thousand times sweeter on a weight basis [28].Single-
chain monellin (SCM),which is an engineered 94-residue
polypeptide,has proven to be as sweet as native two-
chain monellin,and is more stable than the native monellin
at high temperature and in acidic environments [33].
Native monellin is relatively sensitive to heat or acid treatment,
which may cause separation of the sub-units and
denaturation of the protein.Despite misgivings about the
stability of the protein to heat and acid,downstream processes
have been established.Its D-enantiomer has been
crystallized and analyzed by X-ray crystallography at 1.8
resolution.Two crystal forms (I and II) were found under
crystallization conditions similar,but not identical,to the
crystallization conditions of natural L-monellin [34].One
NMR study of a non-sweet analog in which the AspB7 of
protein was replaced by AbuB7 (L-2-Aminobutylicacid),
showed similar 3-dimensional structures of these two proteins,
indicating that the lack of the beta-carboxyl group in
the AbuB7 analog is responsible for the loss of sweetness
[35].Recent research on identifying binding sites on the
英语翻译The protein is approximately 10000 timessweeter than sugar on a molar basis [28].It is a proteinthat tastes intensely sweet only to Old World monkeysand to higher primates,including man [29],as it has beenfound that the protein binds to c
以摩尔浓度为单位,这种蛋白质大约比蔗糖要甜10000倍.仅仅对于旧世纪猴和包括人类在内的更高等的灵长类来说,这种蛋白质尝起来非常甜[29],因为据发现这种蛋白质会与恒河猴叶状乳突味孔内的某种元素形成化学键[30].索马甜(一种甜蛋白)已在很多国家被批准用作增味剂和高强度甜味剂[31].
莫纳林
莫纳林(一种甜蛋白)由两条联合非共价多肽链组成——一条含44个氨基酸残基的A肽链和一条含50个氨基酸残基的B肽链[32].这种蛋白质能从在生长在西部非洲的一种防己科水果Dioscoreophyllum cumminsii中提纯出来.这种蛋白质以摩尔浓度为单位大约比蔗糖甜100,000倍,以重量为单位大约比蔗糖甜几千倍[28].工业合成的含94个氨基酸残基的单肽链莫纳林蛋白(SCM)已被证实和天然双链莫纳林蛋白一样甜,而且在高温环境和酸性环境中更加稳定[33].
天然莫纳林蛋白对热处理和酸处理比较敏感,这有可能导致亚基分离和蛋白质变性.尽管对于这种蛋白质在热酸环境中的稳定性还有疑虑,顺流处理工序已经被建立.它的D-璇光对映异构体已被结晶,并且在1.分辨率用X射线晶体解析.在结晶化的状态下两种晶体形态(I和II)相似,但与天然L-莫纳林蛋白的晶体形态并非完全相同[34].一项对以AbuB7 (L-2-Aminobutylicacid)取代该蛋白质中AspB7的无甜度类似物的核磁共振研究表明这两种蛋白质具有类似的三维结构,说明甜度的消失是由于AbuB7类似物中缺失beta-carboxyl组[35].最近关于鉴别在……上结合点的研究
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蛋白质,约10000 糖酸比28的基础上臼齿. 这是蛋白质 这只是旧世界甜口味激烈猴子 灵长类与高,包括29名男子,因为这已 发现蛋白质分子具有某些味道 猴型的毛细孔foliatepapillae[30]. 基 已获许多国家所使用的一种味道 增强和高强度特性31. monellin monellin、甜蛋白质,由两个nonco...
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蛋白质,约10000 糖酸比28的基础上臼齿. 这是蛋白质 这只是旧世界甜口味激烈猴子 灵长类与高,包括29名男子,因为这已 发现蛋白质分子具有某些味道 猴型的毛细孔foliatepapillae[30]. 基 已获许多国家所使用的一种味道 增强和高强度特性31. monellin monellin、甜蛋白质,由两个noncovalently 相关polypeptide链,44链氨基 残余酸和B链50个氨基酸残留32. 蛋白质可以从净化成果Dioscoreophyllum 西非和Cumminsii增长约为 糖酸比10万倍的基础上,对臼齿 陈重的几千倍的基础[28]. 单 链monellin(治安法官最高),这是一个策划94-残留 polypeptide,已被证明是甜的,以两 链monellin,是比较稳定的本土monellin 在高温和酸性环境33. 本土monellin比较敏感或热酸治疗 这可能造成分裂分单位 变性的蛋白质. 尽管担心 蛋白质的热稳定性和酸、下游过程 已经建立. 其D已enantiomer 具体分析和X射线结晶180? 决议. 两个水晶表(一、二)发现在 结晶情况类似,但不完全相同,给 自然条件结晶L-34monellin. 一 高科技研究非甜的模拟,aspb7 abub7改为蛋白(L-2-AMINOBUTYLICACID) 显示类似立体结构,这两种蛋白质 显示缺乏试用羧集团 abub7模拟的损失负责甜头 35. 最近的研究确定场址的约束力
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