Neuraminidase enzyme kinetics parameters of influenza viruses.

aVirus infectivity was determined by plaque assay in MDCK cells. Values are expressed in log10 PFU/mL (mean ± SD) from 3 independent determinations.bResults represent the means ± SD from 7 independent determinations for A/PR/8/34 (H1N1) virus and 4 independent determinations for A/CA/04/09 (H1N1pdm09) and B/WIS/01/10 viruses.cPercent increase of values as calculated after the correction for spectroscopic MUNANA interference. The increases in Vmax and Km values after correction were statistically significant (Pt-test).