Faculty Advisor

Adams, David S.


The hemagglutinin-neuraminidase (HN) glycoprotein of Newcastle Disease Virus (NDV) is responsible for both the attachment and the sialidase activities of the virus, along with playing a multi-faceted role in the promotion of membrane fusion by the fusion protein (F). The sites responsible for these activities have not yet been identified in detail, although several regions important to those functions have been determined. Site-directed mutagenesis was used to introduce the mutation, I175E into the HN protein. As expected from comparison with the influenza NA protein, I175E-mutated HN is deficient in NA activity. However, it also lacks receptor binding and, consequently, fusion promoting activity. To test the possibility that the lack of receptor binding is due to steric hindrance of the attachment site resulting from failure to completely trim sialic acid from the protein's glycosyl groups, deletion of individual glycoprotein groups from the mutant was performed. Each of these failed to restore attachment, suggesting that I175 may play a role in attachment, as well as NA.


Worcester Polytechnic Institute

Date Accepted

January 1999



Project Type

Major Qualifying Project


Restricted-WPI community only

Advisor Department

Biology and Biotechnology