Amino acid sequence analysis and identification of mutations under positive selection in hemagglutinin of 2009 influenza A (H1N1) isolates.
Summary of "Amino acid sequence analysis and identification of mutations under positive selection in hemagglutinin of 2009 influenza A (H1N1) isolates."
The 2009 flu pandemic is caused by a new strain of influenza A (H1N1) virus, A/H1N1/09. With its high transmissibility, this novel virus has caused a pandemic and infected over 600,000 people globally. By comparing the hemaglutinin (HA) gene and protein sequences among over 700 A/H1N1/09 isolates, mutations in the receptor-binding sites and antigenic epitope regions were identified. Among these mutations, T220 and E/G239 were found to be strongly positively selected over the course of spreading of the A/H1N1/09 virus worldwide. Interestingly, both sites are located in the highly variable epitope regions of HA1, and residue 239 also plays an important role in the receptor-binding process. Further analyses demonstrated that the percentage of T220 mutants among all isolates increased rapidly during the evolution, and that an E/G239 mutation could decrease the binding affinity of the virus with its cellular receptor. Thus, due to a potential functional importance of residues 220 and 239, mutations at these sites, as well as the significant of positive selection on these sites deserves more attention, while new vaccines and therapeutic drugs are developed against this novel virus.
Key Laboratory of Tropical Disease Control, Ministry of Education, Sun Yat-Sen University, Guangzhou, China.
This article was published in the following journal.
Name: Virus genes
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/20809098
- DOI: http://dx.doi.org/10.1007/s11262-010-0526-z
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Medical and Biotech [MESH] Definitions
A process that includes the determination of an amino acid sequence of a protein (or peptide, oligopeptide or peptide fragment) and the information analysis of the sequence.
MOLECULAR BIOLOGY techniques used in the diagnosis of disease. Included are such techniques as IN SITU HYBRIDIZATION of chromosomes for CYTOGENETIC ANALYSIS; OLIGONUCLEOTIDE ARRAY SEQUENCE ANALYSIS of gene expression patterns in disease states; identification of pathogenic organisms by analysis of species specific DNA sequences; and detection of mutations with POLYMERASE CHAIN REACTION.
A theoretical representative nucleotide or amino acid sequence in which each nucleotide or amino acid is the one which occurs most frequently at that site in the different sequences which occur in nature. The phrase also refers to an actual sequence which approximates the theoretical consensus. A known CONSERVED SEQUENCE set is represented by a consensus sequence. Commonly observed supersecondary protein structures (AMINO ACID MOTIFS) are often formed by conserved sequences.
A multistage process that includes the determination of a sequence (protein, carbohydrate, etc.), its fragmentation and analysis, and the interpretation of the resulting sequence information.
One of the endogenous pentapeptides with morphine-like activity. It differs from LEU-ENKEPHALIN by the amino acid METHIONINE in position 5. Its first four amino acid sequence is identical to the tetrapeptide sequence at the N-terminal of BETA-ENDORPHIN.