tetano
Editor, Senior Moderator
Adv Appl Bioinform Chem. 2014 Oct 3;7:37-44. doi: 10.2147/AABC.S68934. eCollection 2014.
The hemagglutinin of the influenza A(H1N1)pdm09 is mutating towards stability.
Castel?n-Vega JA, Maga?a-Hern?ndez A, Jim?nez-Alberto A, Ribas-Aparicio RM.
Author information
Abstract
The last influenza A pandemic provided an excellent opportunity to study the adaptation of the influenza A(H1N1)pdm09 virus to the human host. Particularly, due to the availability of sequences taken from isolates since the beginning of the pandemic until date, we could monitor amino acid changes that occurred in the hemagglutinin (HA) as the virus spread worldwide and became the dominant H1N1 strain. HA is crucial to viral infection because it binds to sialidated cell-receptors and mediates fusion of cell and viral membranes; because antibodies that bind to HA may block virus entry to the cell, this protein is subjected to high selective pressure. Multiple alignment analysis of sequences of the HA from isolates taken since 2009 to date allowed us to find amino acid changes that were positively selected as the pandemic progressed. We found nine changes that became prevalent: HA1 subunits D104N, K166Q, S188T, S206T, A259T, and K285E; and HA2 subunits E47K, S124N, and E172K. Most of these changes were located in areas involved in inter- and intrachain interactions, while only two (K166Q and S188T) were located in known antigenic sites. We conclude that selective pressure on HA was aimed to improve its functionality and hence virus fitness, rather than at avoidance of immune recognition.
KEYWORDS:
hemagglutinin evolution; influenza A; virus fitness
PMID:
25328411
[PubMed]
PMCID:
PMC4198066
Free PMC Article
http://www.ncbi.nlm.nih.gov/pubmed/25328411
The hemagglutinin of the influenza A(H1N1)pdm09 is mutating towards stability.
Castel?n-Vega JA, Maga?a-Hern?ndez A, Jim?nez-Alberto A, Ribas-Aparicio RM.
Author information
Abstract
The last influenza A pandemic provided an excellent opportunity to study the adaptation of the influenza A(H1N1)pdm09 virus to the human host. Particularly, due to the availability of sequences taken from isolates since the beginning of the pandemic until date, we could monitor amino acid changes that occurred in the hemagglutinin (HA) as the virus spread worldwide and became the dominant H1N1 strain. HA is crucial to viral infection because it binds to sialidated cell-receptors and mediates fusion of cell and viral membranes; because antibodies that bind to HA may block virus entry to the cell, this protein is subjected to high selective pressure. Multiple alignment analysis of sequences of the HA from isolates taken since 2009 to date allowed us to find amino acid changes that were positively selected as the pandemic progressed. We found nine changes that became prevalent: HA1 subunits D104N, K166Q, S188T, S206T, A259T, and K285E; and HA2 subunits E47K, S124N, and E172K. Most of these changes were located in areas involved in inter- and intrachain interactions, while only two (K166Q and S188T) were located in known antigenic sites. We conclude that selective pressure on HA was aimed to improve its functionality and hence virus fitness, rather than at avoidance of immune recognition.
KEYWORDS:
hemagglutinin evolution; influenza A; virus fitness
PMID:
25328411
[PubMed]
PMCID:
PMC4198066
Free PMC Article
http://www.ncbi.nlm.nih.gov/pubmed/25328411