Influenza A H5N1 (A/Hong kong/213/2003) Hemagglutinin/HA Protein (S28W, RRRKKR to TETR, uncleaved, His) is expressed in HEK293 mammalian cells with His tag. The predicted molecular weight is 60 kDa and the accession number is Q4H2E2.

H5N1

HEK293 Cells

Harvey rat sarcoma viral oncogene homolog

A DNA sequence encoding the extracellular domain (Met 1-Gln 531) (28 Ser/Trp mutation) of the influenza hemagglutinin (A/Hong kong/213/2003 (H5N1)) (ABP51975.1) (HA1+HA2, cleavage site mutated RRRKKR-TETR, uncleaved), was expressed, fused with a C-terminal polyhistidine tag. Predicted N terminal: Asp 17

> 90 % as determined by SDS-PAGE

A Certificate of Analysis (CoA) containing reconstitution instructions is included with the products. Please refer to the CoA for detailed information.

It is recommended to store recombinant proteins at -20°C to -80°C for future use. Lyophilized powders can be stably stored for over 12 months, while liquid products can be stored for 6-12 months at -80°C. For reconstituted protein solutions, the solution can be stored at -20°C to -80°C for at least 3 months. Please avoid multiple freeze-thaw cycles and store products in aliquots.

The influenza viral Hemagglutinin (HA) protein is a homotrimer with a receptor binding pocket on the globular head of each monomer.HA has at least 18 different antigens. These subtypes are named H1 through H18.HA has two functions. Firstly, it allows the recognition of target vertebrate cells, accomplished through the binding to these cells' sialic acid-containing receptors. Secondly, once bound it facilitates the entry of the viral genome into the target cells by causing the fusion of the host endosomal membrane with the viral membrane. The influenza virus Hemagglutinin (HA) protein is translated in cells as a single protein, HA, or hemagglutinin precursor protein. For viral activation, hemagglutinin precursor protein (HA) must be cleaved by a trypsin-like serine endoprotease at a specific site, normally coded for by a single basic amino acid (usually arginine) between the HA1 and HA2 domains of the protein. After cleavage, the two disulfide-bonded protein domains produce the mature form of the protein subunits as a prerequisite for the conformational change necessary for fusion and hence viral infectivity.