油菜籽在食品和燃料工业中起着至关重要的作用。由于氨基肽酶参与了所有生物的许多生理过程,因此重要的是了解其在经济相关植物中的作用和特性。筛选未发芽的冬季油菜种子的提取物的氨肽酶活性。确定了底物特异性,pH和温度的影响以及蛋白酶抑制剂和所选金属离子对氨基肽酶活性的影响。通过NATIVE-PAGE和SDS-PAGE电泳估计的大约分子量为〜60 kDa。粗提物中存在的部分纯化的酶以及氨基肽酶优先裂解为Phe- p不适用 还确定了对几种底物的活性曲线。以Phe- p NA为底物,在pH 6.5和40°C的温度下观察到最大活性。pH曲线中朝向Phe- p NA的两个可见斑点,以及其他结果(IEF)表明,存在一种以上分子量相似的氨基肽酶。对于Leu-和Ala- p NA作为底物,观察到更低的活性和更宽的pH分布。
A convenient synthesis of amino acid p-nitroanilides; synthons in the synthesis of protease substrates
作者:Dirk T.S. Rijkers、Hans P.H.M. Adams、H. Coenraad Hemker、Godefridus I. Tesser
DOI:10.1016/0040-4020(95)00671-t
日期:1995.10
A method is described for the synthesis of Nα-protected bi- and trifunctional aminoacid p-nitroanilides. The reaction uses phosphorus oxychloride as the condensing agent. The synthesis is simple, rapid, free of racemization and affords yields between 70–90%. The synthesis can be performed not only with aminoacid derivatives of the urethane type including acid-labile (Z. Boc) and base-labile (Fmoc
Synthesis of β-Hydroxy α-Amino Acids Through Brønsted Base-Catalyzed <i>syn</i>-Selective Direct Aldol Reaction of Schiff Bases of Glycine <i>o</i>-Nitroanilide
作者:Silvia Vera、Ana Vázquez、Ricardo Rodriguez、Sandra del Pozo、Iñaki Urruzuno、Abel de Cózar、Antonia Mielgo、Claudio Palomo
DOI:10.1021/acs.joc.1c00406
日期:2021.6.4
Here we report the highly enantio- and syn-selective synthesis of β-hydroxy α-amino acids from glycine imine derivatives under Brønsted base (BB) catalysis. The key of this approach is the use of benzophenone-derived imine of glycine o-nitroanilide as a pronucleophile, where the o-nitroanilide framework provides an efficient hydrogen-bonding platform that accounts for nucleophile reactivity and diastereoselectivity