Both α2,3- and α2,6-Linked Sialic Acids on O-Linked Glycoproteins Act as Functional Receptors for Porcine Sapovirus

• DOI: 10.1371/journal.ppat.1004172
• Publication Date: 2014-06-05T16:55:00Z
• Authors: Deok-Song Kim; Myra Hosmillo; Mia Madel Alfajaro; Ji-Yun Kim; Jun-Gyu Park; Kyu-Yeol Son; Eun-Hye Ryu; Frederic Sorgeloos; Hyung-Jun Kwon; Su-Jin Park; Woo Song Lee; Duck Cho; Joseph Kwon; Jong-Soon Choi; Mun-Il Kang; Ian Goodfellow; Kyoung-Oh Cho
• Keywords: Sapovirus; Neuraminic acid; Sialidase

Sapovirus, a member of the Caliciviridae family, is an important cause acute gastroenteritis in humans and pigs. Currently, porcine sapovirus (PSaV) Cowden strain remains only cultivable Sapovirus genus. While some caliciviruses are known to utilize carbohydrate receptors for entry infection, functional receptor unknown. To characterize PSaV, we undertook comprehensive series protein-ligand biochemical assays mock PSaV-infected cell culture and/or piglet intestinal tissue sections. PSaV revealed neither hemagglutination activity with red blood cells from any species nor binding synthetic histo-blood group antigens, indicating that does not use antigens as receptors. Attachment infection were markedly blocked by sialic acid Vibrio cholerae neuraminidase (NA), suggesting role α2,3-linked, α2,6-linked or α2,8-linked virus attachment. However, viral attachment partially inhibited treatment sialidase S (SS) Maackia amurensis lectin (MAL), both specific α2,3-linked acid, Sambucus nigra (SNL), acid. These results indicated recognizes α2,3- acids infection. Treatment proteases benzyl 4-O-β-D-galactopyranosyl-β-D-glucopyranoside (benzylGalNAc), which inhibits O-linked glycosylation, also reduced whereas inhibition glycolipd synthesis N-linked glycosylation had no such effect on data suggest binds cellular consist glycoproteins attached via glycosylation.