Liu Lin, Prudden Anthony R, Bosman Gerlof P, Boons Geert-Jan
Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA.
Chemical Biology and Drug Discovery, Utrecht University, 3584 CG Utrecht, The Netherlands; Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3584 CG Utrecht, The Netherlands.
Carbohydr Res. 2017 Nov 27;452:122-128. doi: 10.1016/j.carres.2017.10.001. Epub 2017 Oct 12.
Sialylglycopeptide (SGP) is a complex bi-antennary N-glycan bearing a short peptide fragment that can be isolated from the yolk of hen eggs. This natural product has gained popularity as a starting material for the semi-synthesis of N-glycans. We have found that current isolation methods provide a glycopeptide contaminated with several related structures, one being a glycopeptide having a hexose directly attached to peptide backbone, most like through the hydroxyl containing side chain of the threonine moiety. Furthermore, current methods employ fresh egg yolks that need to be lyophilized and involve several tedious purification steps. Herein, we report a convenient method for the isolation of gram quantities of homogeneous SGP from commercially available egg yolk powder using solid/liquid extraction and HILIC-HPLC purification.
唾液酸糖肽（SGP）是一种复杂的双触角N-聚糖，带有一个短肽片段，可从鸡蛋蛋黄中分离得到。这种天然产物作为N-聚糖半合成的起始原料已受到广泛关注。我们发现，目前的分离方法得到的糖肽被几种相关结构污染，其中一种是己糖直接连接到肽主链上的糖肽，很可能是通过苏氨酸部分含羟基的侧链连接。此外，目前的方法使用需要冻干的新鲜蛋黄，并且涉及几个繁琐的纯化步骤。在此，我们报道了一种从市售蛋黄粉中分离克级均一SGP的简便方法，该方法采用固/液萃取和亲水相互作用液相色谱-高效液相色谱（HILIC-HPLC）纯化。
