非酶促转氨测定蛋白质相对分子量及研究空间结构的变化

在非酶促转氨过程中测定生成甘氨酸的量，计算蛋白质的相对分子量是一种方便、节省经费和快速的方法，该方法的应用不受蛋白分子量大小的限制。非酶促转氨的另一产物２－羰化氨基酸可作为制备各种喹喔啉衍生物的原料。苯丙氨酸非酶促形成的苯丙酮酸与邻苯二胺反应生成３－苯基－２－羰基喹喔啉。该产物在３６３ｎｍ具有荧光发色性质。胰岛素及不同一级结构的短肽２－羰酰衍生物和２－喹喔啉衍生物的荧光在盐酸胍和不同ＰＨ训的变化各

USING NON-ENZYMATIC TRANSAMINATION TO MEASURE THE RELATIVE MOLECULAR MASS OF PROTEINS, SYNTHESIZE QUINOXALINE DERIVATIVES AND STUDY CONFORMATIONAL CHANGES

A proedure for protein fornsamination and removing the transaminated N-terminal residue has been used for studying structure-function relationships (Dixon and Fields, Met.Enzymol. 25, 1972, 409). It was shown to be convenient to determine the relative molecular masses of protein chains by measuring the glycine formed from glyoxylate during transamination. Quinoxaline derivatives have been synthesized by the reaction of 2-oxo acids from amino ads with o-phenylenediamine. Moreover 2-oxo acids from group. the emission maximum of 3-benzyl-2-hydroxyquinoxaline from the reaction of o-phenylenediamine with phenylpyruvate is at 405nm. The fluorescent derivahves have been used to study conformaional changes in insulin and peptides, and determination of whether N-terminals of gGAPDH are blocked by the glycation or not.