[Viral glycosyltransferases]

During the last decades, advances in cellular biology highlighted the crucial roles of glycans in numerous important biological processes, raising the concept of glycomics, which is currently considered to be complementary to genomics, transcriptomics and proteomics.Viruses are forced parasites, depending on and interfering with the host cell machinery. Studies of the last decade revealed that viruses have acquired the capability to interfere with the glycome at their own benefit. The study of the glycans resulting from viral infection and their functions is called « Glycovirology ». One of the most fascinating aspects of glycovirology is the study of how viruses affect the glycome. Viruses reach that goal either by affecting the expression of host glycosyltransferases, or by expressing their own glycosyltransferases. Up to now, viral glycosyltransferases have been reported in one herpesvirus and several poxviruses, baculoviruses, phycodnaviruses and bacteriophages. In this review, viral glycosyltransferases will be described exhaustively and their established or putative functions will be discussed. The description of those enzymes illustrates several fundamental aspects of virology.