%0 Journal Article %A Manoharan, Vinoth K. %A Khattar, Sunil K. %A Paldurai, Anandan %A Kim, Shin-Hee %A Samal, Siba K. %T A Y527A mutation in the fusion protein of Newcastle disease virus strain LaSota leads to a hyperfusogenic virus with increased replication and immunogenicity %D 2016 %J Journal of General Virology, %V 97 %N 2 %P 287-292 %@ 1465-2099 %R https://doi.org/10.1099/jgv.0.000350 %I Microbiology Society, %X Newcastle disease is a highly contagious and economically important disease of poultry. Low-virulence Newcastle disease virus (NDV) strains such as B1 and LaSota have been used as live vaccines, with a proven track record of safety and efficacy. However, these vaccines do not completely prevent infection or virus shedding. Therefore, there is a need to enhance the immunogenicity of these vaccine strains. In this study, the effect of mutations in the conserved tyrosine residues of the F protein of vaccine strain LaSota was investigated. Our results showed that substitution of tyrosine at position 527 by alanine resulted in a hyperfusogenic virus with increased replication and immunogenicity. Challenge study with highly virulent NDV strain Texas GB showed that immunization of chickens with Y527A mutant virus provided 100 % protection and no shedding of the challenge virus. This study suggests that the strain LaSota harbouring the Y527A mutation may represent a more efficacious vaccine. %U https://www.microbiologyresearch.org/content/journal/jgv/10.1099/jgv.0.000350