Abstract: E2 is one of the three envelope glycoproteins of Classical Swine Fever Virus (CSFV). E2 is involved in several functions including virus attachment and entry to target cells, production of antibodies, induction of protective immune response in swine, and virulence. Seven putative glycosylation sites in E2 were modified by site directed mutagenesis of a CSFV Brescia infectious clone (BICv). A panel of virus mutants was obtained and used to investigate whether the removal of putative glycosylation sites in the E2 glycoprotein would affect viral virulence/pathogenesis in swine. We observed that rescue of viable virus was completely impaired by removal of all putative glycosylation sites in E2, but restored when mutation N185A reverted to wild-type asparagine produced viable virus that was attenuated in swine. Single mutations of each of the E2 glycosylation sites showed that amino acid N116 (N1v virus) was responsible for BICv attenuation.

Abstract: E1, along with Erns and E2 is one of the three envelope glycoproteins of Classical Swine Fever Virus (CSFV). Our previous studies indicated that glycosylation status of either E2 or Erns strongly influence viral virulence in swine. Here, we have investigated the role of E1 glycosylation of highly virulent CSFV strain Brescia during infection in the natural host. The three putative glycosylation sites in E1 were modified by site directed mutagenesis of a CSFV Brescia infectious clone (BICv). A panel of virus mutants was obtained and used to investigate whether the removal of putative glycosylation sites in the E1 glycoprotein would affect viral virulence/pathogenesis in swine. We observed that rescue of viable virus was completely impaired by removal of all three putative glycosylation sites in E1. Single mutations of each of the E1 glycosylation sites showed that CSFV amino acid N594 (E1.N3 virus), as well the combined mutation of N500 and N513 (E1.N1N2 virus) resulted in BICv attenuation.

Abstract: E1, along with Erns and E2 is one of the three envelope glycoproteins of Classical Swine Fever Virus (CSFV). Our previous studies indicated that glycosylation status of either E2 or Erns strongly influence viral virulence in swine. Here, we have investigated the role of E1 glycosylation of highly virulent CSFV strain Brescia during infection in the natural host. The three putative glycosylation sites in E1 were modified by site directed mutagenesis of a CSFV Brescia infectious clone (BICv). A panel of virus mutants was obtained and used to investigate whether the removal of putative glycosylation sites in the E1 glycoprotein would affect viral virulence/pathogenesis in swine. We observed that rescue of viable virus was completely impaired by removal of all three putative glycosylation sites in E1. Single mutations of each of the E1 glycosylation sites showed that CSFV amino acid N594 (E1.N3 virus), as well the combined mutation of N500 and N513 (E1.N1N2 virus) resulted in BICv attenuation.

Abstract: E2 is one of the three envelope glycoproteins of Classical Swine Fever Virus (CSFV). E2 is involved in several functions including virus attachment and entry to target cells, production of antibodies, induction of protective immune response in swine, and virulence. Seven putative glycosylation sites in E2 were modified by site directed mutagenesis of a CSFV Brescia infectious clone (BICv). A panel of virus mutants was obtained and used to investigate whether the removal of putative glycosylation sites in the E2 glycoprotein would affect viral virulence/pathogenesis in swine. We observed that rescue of viable virus was completely impaired by removal of all putative glycosylation sites in E2, but restored when mutation N185A reverted to wild-type asparagine produced viable virus that was attenuated in swine. Single mutations of each of the E2 glycosylation sites showed that amino acid N116 (N1v virus) was responsible for BICv attenuation.

Abstract: E2 is one of the three envelope glycoproteins of Classical Swine Fever Virus (CSFV). E2 is involved in several functions including virus attachment and entry to target cells, production of antibodies, induction of protective immune response in swine, and virulence. Seven putative glycosylation sites in E2 were modified by site directed mutagenesis of a CSFV Brescia infectious clone (BICv). A panel of virus mutants was obtained and used to investigate whether the removal of putative glycosylation sites in the E2 glycoprotein would affect viral virulence/pathogenesis in swine. We observed that rescue of viable virus was completely impaired by removal of all putative glycosylation sites in E2, but restored when mutation N185A reverted to wild-type asparagine produced viable virus that was attenuated in swine. Single mutations of each of the E2 glycosylation sites showed that amino acid N116 (N1v virus) was responsible for BICv attenuation.

Abstract: E1, along with Erns and E2 is one of the three envelope glycoproteins of Classical Swine Fever Virus (CSFV). Our previous studies indicated that glycosylation status of either E2 or Erns strongly influence viral virulence in swine. Here, we have investigated the role of E1 glycosylation of highly virulent CSFV strain Brescia during infection in the natural host. The three putative glycosylation sites in E1 were modified by site directed mutagenesis of a CSFV Brescia infectious clone (BICv). A panel of virus mutants was obtained and used to investigate whether the removal of putative glycosylation sites in the E1 glycoprotein would affect viral virulence/pathogenesis in swine. We observed that rescue of viable virus was completely impaired by removal of all three putative glycosylation sites in E1. Single mutations of each of the E1 glycosylation sites showed that CSFV amino acid N594 (E1.N3 virus), as well the combined mutation of N500 and N513 (E1.N1N2 virus) resulted in BICv attenuation.