Insect Cell Hosts for Baculovirus Expression Vectors Contain Endogenous Exoglycosidase Activity

摘要

AbstractFour different insect cell lines that can be used as hosts for baculovirus infection were assayed for the presence of endogenous exoglycosidases. All four cell lines, derived fromSpodoptera frugiperda, Trichoplusia ni, Bombyx mori, orMalacosoma disstria, containedN‐acetyl‐β‐glucosaminidase,N‐acetyl‐β‐galactosaminidase, β‐galactosidase, and sialidase activities. Exoglycosidase activities were found in cell lysates as well as cell‐free supernatants from uninfected and wild‐type baculovirus infected cells. Oligosaccharide analysis of cellular glycoproteins using lectins recognizing Galβ1, 3GalNAc, Galβ1, 4GlcNAc, and NeuAcα2, 6Gal demonstrated that only Galβ1,3GalNAc was present. The demonstration that these cells contain exoglycosidases raises the possibility that the oligosaccharides of baculovirus‐expressed glycoproteins are subjec