Influenza neuraminidase is an enzyme that promotes the spread of influenza virus among host cells. It is the target of oseltamivir and related antiviral drugs. The image shows tetramers of neuraminidase (Protein Data Bank entry 3k3a) styled as flowers. Three tetramers are colored pink, with a central metal ion in white and nearby residues in yellow, and a fourth tetramer is colored green to resemble leaves. Each monomer or “petal” is a six-bladed β-propeller. A simple, line-drawing-like appearance is obtained with ambient lighting mode and silhouettes.
The structure is described more fully in the following:
Structural and functional basis of resistance to neuraminidase inhibitors of influenza B viruses. Oakley AJ, Barrett S, Peat TS, Newman J, Streltsov VA, Waddington L, Saito T, Tashiro M, McKimm-Breschkin JL. J Med Chem. 2010 Sep 9;53(17):6421-31.© 2011 The Regents of the University of California; all rights reserved.