Institute of Chemistry and Biochemistry, Organic Chemistry, Freie University Berlin, 14195 Berlin, Germany.
Bioorg Med Chem. 2013 Jun 15;21(12):3542-6. doi: 10.1016/j.bmc.2013.03.051. Epub 2013 Apr 2.
Several factors reduce the efficacy of natural peptides as drug candidates; chief among these is their rapid digestion by human proteases. Over the last few decades, a number of strategies have been employed to increase the enzymatic stability of peptides, including the introduction of non-natural amino acids. This study aims at the investigation of the effect of side chain fluorination on the stability of peptides in human blood plasma. Ten model peptides with different non-natural amino acids were designed, synthesized and subjected to enzymatic degradation in human blood plasma. The stability of the studied peptides was followed by HPLC analysis and compared to the control peptide built with only proteinogenic residues. Four main hydrolysis products were detected and identified by mass spectrometry, three of them being characteristic cleavage products of the serine protease Elastase. A final enzymatic study with isolated Elastase validated then the outcome of the plasma study. This case study contributes to the application of fluorinated amino acids in the design of proteolytically stable peptides and proteins with potential clinical relevance.
几种因素降低了天然肽作为药物候选物的功效；其中主要的是它们被人体蛋白酶迅速消化。在过去的几十年中，已经采用了许多策略来提高肽的酶稳定性，包括引入非天然氨基酸。本研究旨在研究侧链氟化对肽在人血浆中稳定性的影响。设计、合成了具有不同非天然氨基酸的十个模型肽，并在人血浆中进行酶降解。通过 HPLC 分析和与仅用蛋白质残基构建的对照肽进行比较，跟踪研究肽的稳定性。通过质谱检测和鉴定了四个主要的水解产物，其中三个是丝氨酸蛋白酶弹性蛋白酶的特征切割产物。最后用分离的弹性蛋白酶进行的酶学研究验证了血浆研究的结果。该案例研究有助于将氟化氨基酸应用于设计具有潜在临床相关性的肽和蛋白质，以提高其对蛋白水解的稳定性。
