Influenza D virus (IDV) utilizes bovines as a primary reservoir with periodical spillover to other mammalian hosts. By using traditional hemagglutination assay coupled with sialoglycan microarray (SGM) platform and functional assays, we demonstrated that IDV is more efficient in recognizing both 9-O-acetylated N-acetylneuraminic acid (Neu5,9Ac2) and 9-O-acetylated N-glycolylneuraminic acid (Neu5Gc9Ac) than influenza C virus (ICV), a ubiquitous human pathogen. ICV seems to strongly prefer Neu5,9Ac2 over Neu5Gc9Ac. Since Neu5Gc9Ac is different from Neu5,9Ac2 only by an additional oxygen in the group at the C5 position, our results reveal that the hydroxyl group in Neu5Gc9Ac plays a critical role in determining receptor binding specificity, which as a result may discriminate IDV from ICV in communicating with 9-O-acetylated SAs. These findings shall provide a framework for further investigation towards better understanding of how newly discovered multiple-species-infecting IDV exploits natural 9-O-acetylated SA variations to expand its host range.

中文翻译：

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D 型流感病毒在识别含有 9-O-乙酰化 N-乙酰基-或 N-乙醇酰基-神经氨酸的聚糖受体方面不同于其相关的 C 型流感病毒。


D 型流感病毒 (IDV) 利用牛作为主要宿主，并定期溢出到其他哺乳动物宿主。通过使用传统的血凝试验结合唾液酸聚糖微阵列 (SGM) 平台和功能试验，我们证明 IDV 能够更有效地识别 9-O-乙酰化 N-乙酰神经氨酸 (Neu5,9Ac2) 和 9-O-乙酰化 N-乙酰神经氨酸酸（Neu5Gc9Ac）比丙型流感病毒（ICV），一种普遍存在的人类病原体。 ICV 似乎更喜欢 Neu5,9Ac2 而不是 Neu5Gc9Ac。由于 Neu5Gc9Ac 与 Neu5,9Ac2 的不同之处仅在于 C5 位置上的基团中多了一个氧，因此我们的结果表明 Neu5Gc9Ac 中的羟基在确定受体结合特异性方面起着关键作用，因此可能将 IDV 与 ICV 区分开来。与 9-O-乙酰化 SA 通信。这些发现将为进一步研究提供一个框架，以便更好地了解新发现的多物种感染 IDV 如何利用天然 9-O-乙酰化 SA 变异来扩大其宿主范围。