Sialic Acid Binding Properties of Soluble Coronavirus Spike (S1) Proteins: Differences between Infectious Bronchitis Virus and Transmissible Gastroenteritis Virus

Viruses

Katarina Shahwan¹  Martina Hesse¹  Ann-Kathrin Mork¹  Georg Herrler¹ 

[1] Institute of Virology University of Veterinary Medicine Hannover, Germany;

关键词: Coronavirus;    spike protein;    sialic acid receptor;    TGEV;    IBV;   

DOI  :  10.3390/v5081924

来源: mdpi

【 摘 要 】

The spike proteins of a number of coronaviruses are able to bind to sialic acids present on the cell surface. The importance of this sialic acid binding ability during infection is, however, quite different. We compared the spike protein of transmissible gastroenteritis virus (TGEV) and the spike protein of infectious bronchitis virus (IBV). Whereas sialic acid is the only receptor determinant known so far for IBV, TGEV requires interaction with its receptor aminopeptidase N to initiate infection of cells. Binding tests with soluble spike proteins carrying an IgG Fc-tag revealed pronounced differences between these two viral proteins. Binding of the IBV spike protein to host cells was in all experiments sialic acid dependent, whereas the soluble TGEV spike showed binding to APN but had no detectable sialic acid binding activity. Our results underline the different ways in which binding to sialoglycoconjugates is mediated by coronavirus spike proteins.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.