crystal structure of reovirus attachment protein σ1 in complex with sialylated oligosaccharides在复杂的蛋白质晶体结构的呼肠孤病毒附件σ1 sialylated低聚糖.pdf

Crystal Structure of Reovirus Attachment Protein s1 in Complex with Sialylated Oligosaccharides 1 2,3 2,3¤a 3,4¤b Dirk M. Reiter , Johnna M. Frierson , Elizabeth E. Halvorson , Takeshi Kobayashi , Terence S. Dermody2,3,4*, Thilo Stehle1,4* 1 Interfaculty Institute of Biochemistry, University of Tuebingen, Tuebingen, Germany, 2 Departments of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America, 3 Elizabeth B. Lamb Center for Pediatric Research, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America, 4 Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America Abstract Many viruses attach to target cells by binding to cell-surface glycans. To gain a better understanding of strategies used by viruses to engage carbohydrate receptors, we determined the crystal structures of reovirus attachment protein s1 in complex with a-2,3-sialyllactose, a-2,6-sialyllactose, and a-2,8-di-siallylactose. All three oligosaccharides terminate in sialic acid, which serves as a receptor for the reovirus serotype studied here. The overall structure of s1 resembles an elongated, filamentous trimer. It contains a globular head featuring a compact b-barrel, and a fibrous extension formed by seven repeating units of a triple b-spiral that is interrupted near its midpoint by a short a -helical coiled coil. The carbohydrate- binding site is located between b-spiral repeats two and three, distal from the head. In all three comple