Role of pH in Syncytium Induction and Genome Uncoating of Avian Infectious Bronchitis Coronavirus (IBV)

  • D. Li
  • D. Cavanagh
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 276)


Syncytium formation induced in Vero cells by IBV-Beaudette was optimal at pH 6.7 and absent at pH 7.5. Reduction of IBV-Beaudette replication by ammonium chloride, which raises the pH in endosomes, further indicated that uncoating of the virus genome probably occurred within the acidic environment of endosomes. However, this would not appear to apply to all IBV strains, since one was unaffected by the drug. It would appear that some strains of IBV have the capacity to fuse with the plasma membrane at neutral pH, thereby leading to genome uncoating at that site. Other strains of IBV might also uncoat at the plasma membrane when the extracellular environment is slightly less than pH7.


Ammonium Chloride Vero Cell Semliki Forest Virus Murine Hepatitis Virus Aminoethane Sulfonic Acid 


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Copyright information

© Plenum Press, New York 1990

Authors and Affiliations

  • D. Li
    • 1
  • D. Cavanagh
    • 1
  1. 1.Houghton LaboratoryAFRC Institute for Animal HealthHoughton, Huntingdon CambridgeshireUK

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