Chemical Biology Laboratory, National Cancer Institute, 376 Boyles Street, Building 376, Frederick, Maryland 21702, USA.
J Am Chem Soc. 2010 Jul 21;132(28):9653-62. doi: 10.1021/ja100608w.
Carbohydrate-protein interactions play a critical role in a variety of biological processes, and agonists/antagonists of these interactions are useful as biological probes and therapeutic agents. Most carbohydrate-binding proteins achieve tight binding through formation of a multivalent complex. Therefore, both ligand structure and presentation contribute to recognition. Since there are many potential combinations of structure, spacing, and orientation to consider and the optimal one cannot be predicted, high-throughput approaches for analyzing carbohydrate-protein interactions and designing inhibitors are appealing. In this report, we develop a strategy to vary neoglycoprotein density on a surface of a glycan array. This feature of presentation was combined with variations in glycan structure and glycan density to produce an array with approximately 600 combinations of glycan structure and presentation. The unique array platform allows one to distinguish between different types of multivalent complexes on the array surface. To illustrate the advantages of this format, it was used to rapidly identify multivalent probes for various lectins. The new array was first tested with several plant lectins, including concanavalin A (conA), Vicia villosa isolectin B4 (VVL-B(4)), and Ricinus communis agglutinin (RCA120). Next, it was used to rapidly identify potent multivalent inhibitors of Pseudomonas aeruginosa lectin I (PA-IL), a key protein involved in opportunistic infections of P. aeruginosa , and mouse macrophage galactose-type lectin (mMGL-2), a protein expressed on antigen presenting cells that may be useful as a vaccine targeting receptor. An advantage of the approach is that structural information about the lectin/receptor is not required to obtain a multivalent inhibitor/probe.
碳水化合物-蛋白质相互作用在多种生物过程中起着关键作用，这些相互作用的激动剂/拮抗剂可用作生物探针和治疗剂。大多数碳水化合物结合蛋白通过形成多价复合物实现紧密结合。因此，配体结构和呈现都有助于识别。由于要考虑的结构、间距和方向的潜在组合很多，而且无法预测最佳组合，因此分析碳水化合物-蛋白质相互作用和设计抑制剂的高通量方法很有吸引力。在本报告中，我们开发了一种在聚糖阵列表面改变糖基化蛋白密度的策略。这种呈现方式的特点与聚糖结构和聚糖密度的变化相结合，产生了一个具有约 600 种聚糖结构和呈现组合的阵列。独特的阵列平台允许区分阵列表面上不同类型的多价复合物。为了说明这种格式的优势，它被用于快速鉴定各种凝集素的多价探针。新的阵列首先用几种植物凝集素来测试，包括刀豆球蛋白 A（conA）、野豌豆属异凝集素 B4（VVL-B(4)）和蓖麻凝集素（RCA120）。接下来，它被用于快速鉴定铜绿假单胞菌凝集素 I（PA-IL）的有效多价抑制剂，PA-IL 是一种与铜绿假单胞菌机会性感染相关的关键蛋白，以及鼠巨噬细胞半乳糖型凝集素（mMGL-2），这是一种在抗原呈递细胞上表达的蛋白，可能作为针对受体的疫苗有用。该方法的一个优点是，获得多价抑制剂/探针不需要关于凝集素/受体的结构信息。
