University of Bayreuth, Bioorganic Chemistry, Universitätsstraße 30, 95447, Bayreuth, Germany.
Angew Chem Int Ed Engl. 2021 Dec 1;60(49):25922-25932. doi: 10.1002/anie.202110013. Epub 2021 Nov 2.
Recombinant human erythropoietin (EPO) is the main therapeutic glycoprotein for the treatment of anemia in cancer and kidney patients. The in-vivo activity of EPO is carbohydrate-dependent with the number of sialic acid residues regulating its circulatory half-life. EPO carries three N-glycans and thus obtaining pure glycoforms provides a major challenge. We have developed a robust and reproducible chemoenzymatic approach to glycoforms of EPO with and without sialic acids. EPO was assembled by sequential native chemical ligation of two peptide and three glycopeptide segments. The glycopeptides were obtained by pseudoproline-assisted Lansbury aspartylation. Enzymatic introduction of the sialic acids was readily accomplished at the level of the glycopeptide segments but even more efficiently on the refolded glycoprotein. Biological recognition of the synthetic EPOs was shown by formation of 1:1 complexes with recombinant EPO receptor.
重组人红细胞生成素（EPO）是治疗癌症和肾病患者贫血的主要治疗性糖蛋白。EPO 的体内活性依赖于碳水化合物，唾液酸残基数调节其循环半衰期。EPO 携带三个 N-糖链，因此获得纯糖型是一个主要挑战。我们开发了一种稳健且可重复的化学酶法来获得有和没有唾液酸的 EPO 糖型。EPO 通过两个肽和三个糖肽段的顺序天然化学连接组装而成。糖肽通过拟脯氨酸辅助 Lansbury 天冬氨酸化获得。糖肽段上的唾液酸很容易通过酶法引入，在重折叠糖蛋白上甚至更有效。通过与重组 EPO 受体形成 1:1 复合物，证明了合成 EPO 的生物学识别。
