Submitted to: Avian Diseases
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/1/2002
Publication Date: 10/1/2003
Citation: Yamnikova, S.S., Gambaryan, A.S., Tuzikov, A.B., Bovin, N.V., Matrosovich, M.N., Fedyakina, I.T., Grinev, A.A., Blinov, V.M., Lvov, D.K., Suarez, D.L., Swayne, D.E. 2003. Differences Between HA Receptor-Binding Sites Of Avian Influenza Viruses Isolated From Laridae And Anatidae. Avian Diseases 47:1164-1168. Interpretive Summary: Influenza viruses infect a number of different host species including both birds and mammals. The virus is extremely variable in the surface proteins, including the hemagglutinin and neuraminidase genes. The viruses have been classified into 15 distinct groups for the hemagglutinin grouprs, which are called subtypes. One subtype, H13, has been found primarily in gulls. This is unusual since almost all the other subtypes are found commonly in a large number of wild bird species, including ducks. The hemagglutinin gene was examined to try and understand what was different about the H13 gene compared to other hemagglutinin subtypes. It was found that the H13 subtype preferred to attach to different types of sugars as compared to the other subtypes examined. This differences may explain why the H13 subtype virus preferentially infects gulls and not other species of wild birds. Sequence analysis of the hemagglutinin gene also identified several nucleotides that likely resulted in the ability to replicate in gulls.
Technical Abstract: A comparative study of the receptor binding site (RBS) of the hemagglutinin (HA) of H13 influenza viruses isolated from gulls (family Laridae) and non H13 influenza viruses from ducks (family Anatidae). The affinity of all viruses to N-acetylneuraminic acid (Neu5Aca), 3'sialyllactose (3'SL) and to sialylglycopolymers bearing 3'-sialyl(N-cetyllactosamine) (3'SLN-PAA), [Neu5Aca(2-3)GalB(1-4)][-Fuca(1-3)]GlcNAcB (SLex-PAA) and [Neu5Aca(2-3)GalB(1-3)][-Fuca(1-4)]GlcNAcB (SLea-PAA) was determined. The last three polymer glycoconjugates were synthesized to determine the contribution of the carbohydrate chain after the galactose link to the binding with the viral receptor. The difference in affinity between 3'SL and Neu5Aca in all studied H13 viruses is small, that indicates a less significant role of the galactose moiety in the binding with the receptor. The results of virus binding with polymer sialylglycoconjugates indicate that the method of linking the third monosaccharide moiety and the presence of an extra fucose substitute in this moiety influence binding considerably. For viruses isolated from ducks, the optimal polymer tested was SLea-PAA, i.e. for them, a 1-3 linkage between galactose and glucosamine is optimal. This finding is in accord with the data on H13 viruses isolated from gulls which differ by their ability to interact with polymer sialylglycoconjugates. The affinity to all three polymers is uniform and the presence of GlcNAc-linked fucose does not prevent the binding. Amino acid sequence analysis of the hemagglutinin of six H13 viruses and other hemagglutinin subtypes showed substantial differences in the amino acid sequence of the RBS in H13 viruses.