Siegfried Weber

Learn More
Analysis of the full-length sequences of all eight segments of the German wild-bird H5N1 highly pathogenic avian influenza virus index isolate, A/Cygnus cygnus/Germany/R65/2006, and an H5N1 isolate from a cat (A/cat/Germany/R606/2006) obtained during an outbreak in February 2006 revealed a very high similarity between these two sequences. One amino acid(More)
High-pathogenic avian influenza viruses (HPAIVs) evolve from low-pathogenic precursors specifying the HA serotypes H5 or H7 by acquisition of a polybasic HA cleavage site. As the reason for this serotype restriction has remained unclear, we aimed to distinguish between compatibility of a polybasic cleavage site with H5/H7 HA only and unique predisposition(More)
Infectious pancreatic necrosis virus (IPNV), a member of the BIRNAVIRIDAE: with two double-stranded RNA genome segments, encodes five proteins designated VP1 to VP5. To study the function of the 17 kDa nonstructural protein VP5 during virus replication several mutated IPNV genome segments A were constructed and included in a reverse genetics system for IPNV(More)
Highly pathogenic avian influenza viruses (HPAIV) differ from all other strains by a polybasic cleavage site in their hemagglutinin. All these HPAIV share the H5 or H7 subtype. In order to investigate whether the acquisition of a polybasic cleavage site by an avirulent avian influenza virus strain with a hemagglutinin other than H5 or H7 is sufficient for(More)
Reverse genetics has become pivotal in influenza virus research relying on rapid generation of tailored recombinant influenza viruses. They are rescued from transfected plasmids encoding the eight influenza virus gene segments, which have been cloned using restriction endonucleases and DNA ligation. However, suitable restriction cleavage sites often are not(More)
A recombinant Newcastle disease virus (NDV) expressing H6 hemagglutinin (HA) of a low pathogenic avian influenza virus (LPAIV) was generated by reverse genetics (NDVH6). The H6 open reading frame was inserted as an additional transcription unit between the fusion and hemagglutinin-neuraminidase (HN) gene of lentogenic NDV clone 30. Expression of the foreign(More)
The prime virulence determinant of highly pathogenic avian influenza viruses (HPAIVs) is the polybasic haemagglutinin (HA) cleavage site. However, engineering of a polybasic cleavage site into an avian influenza virus of low pathogenicity does not result in transformation into an HPAIV, indicating the importance of other adaptations. Here, the influence of(More)
During picornavirus infection replication of genomic RNA occurs in membrane-associated ribonucleoprotein complexes. These replication complexes contain different nonstructural viral proteins with mostly unknown function. To examine the function of nonstructural picornaviral proteins in more detail, cDNA of foot-and-mouth-disease virus (FMDV) strain O1(More)