The recombinant polymerases of human influenza virus A/PR/8/34 (H1N1) (PR8) and avian influenza virus A/Turkey/England/1969 (H3N2) (TE) using anti-FLAG M2 affinity resin. After confirming trimeric complexes, enzymatic properties of recombinant polymerases were characterized, including model viral RNA binding, in vitro transcription assays, and cap-snatching activity upon addition of cap1-70 mer vRNA as substrate. Taken together we conclude that 293T cells are a suitable expression system for sufficient amount isolation of functional recombinant influenza viral polymerases with 95% of purity. |