Hediger H, Stevens L, Bradenberger H, Schmid K
Biochem J. 1973 Jul;133(3):551-61. doi: 10.1042/bj1330551.
A new procedure for the qualitative and quantitative determination of asparagine, glutamine and pyrrolidonecarboxylic acid in total enzymic hydrolysates of peptides and glycopeptides based on g.l.c. has been developed. Under the conditions of esterification and trifluoroacetylation N-trifluoroacetylaspartic acid mono-n-butyl ester was formed from asparagine and N-trifluoroacetylglutamic acid mono-n-butyl ester from both glutamine and pyrrolidonecarboxylic acid. To distinguish between the latter two compounds, the esterification was carried out at room temperature yielding 30% of esterified pyrrolidonecarboxylic acid but less than 1% of esterified glutamine. In extending the g.l.c. of amino acids, the previously unknown positions in the g.l.c. elution pattern of the following amino acids could also be reproducibly determined: carboxymethylcysteine, homoserine, hydroxylysine and in-methyl-lysine. Further, certain glycopeptides were investigated and the artifacts due to their carbohydrate moieties were determined.
已开发出一种基于气相色谱法对肽和糖肽的全酶水解产物中天冬酰胺、谷氨酰胺和吡咯烷酮羧酸进行定性和定量测定的新方法。在酯化和三氟乙酰化条件下，天冬酰胺形成N - 三氟乙酰天冬氨酸单正丁酯，谷氨酰胺和吡咯烷酮羧酸均形成N - 三氟乙酰谷氨酸单正丁酯。为区分后两种化合物，酯化在室温下进行，生成30%的酯化吡咯烷酮羧酸，但酯化谷氨酰胺少于1%。在扩展氨基酸的气相色谱分析时，还可重复测定以下氨基酸在气相色谱洗脱图谱中先前未知的位置：羧甲基半胱氨酸、高丝氨酸、羟赖氨酸和ε - 甲基赖氨酸。此外，还对某些糖肽进行了研究，并确定了因其碳水化合物部分产生的假象。
