H1N1 2009 pandemic influenza virus: resistance of the I223R neuraminidase mutant explained by kinetic and structural analysis

DOI: 10.1371/journal.ppat.1002914
PMID: 23028314

Authors: Erhard Van Der Vries (Erasmus Medical Centre) , Patrick J. Collins (Medical Research Council, National Institute for Medical Research) , Sebastien Vachieri (Medical Research Council, National Institute for Medical Research) , Xiaoli Xiong (Medical Research Council, National Institute for Medical Research) , Junfeng Liu (Medical Research Council, National Institute for Medical Research; China Agricultural University) , Phil A. Walker (Medical Research Council, National Institute for Medical Research) , Lesley F. Haire (Medical Research Council, National Institute for Medical Research) , Alan J. Hay (Medical Research Council, National Institute for Medical Research) , Martin Schutten (Erasmus Medical Centre) , Albert D. M. E. Osterhaus (Erasmus Medical Centre) , Steve R. Martin (Medical Research Council, National Institute for Medical Research) , Charles A. B. Boucher (Erasmus Medical Centre) , John J. Skehel (Medical Research Council, National Institute for Medical Research) , Steven Gamblin (Medical Research Council, National Institute for Medical Research)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Plos Pathogens , VOL 8 (9)

State: Published (Approved)
Published: October 2012

Abstract: Two classes of antiviral drugs, neuraminidase inhibitors and adamantanes, are approved for prophylaxis and therapy against influenza virus infections. A major concern is that antiviral resistant viruses emerge and spread in the human population. The 2009 pandemic H1N1 virus is already resistant to adamantanes. Recently, a novel neuraminidase inhibitor resistance mutation I223R was identified in the neuraminidase of this subtype. To understand the resistance mechanism of this mutation, the enzymatic properties of the I223R mutant, together with the most frequently observed resistance mutation, H275Y, and the double mutant I223R/H275Y were compared. Relative to wild type, KM values for MUNANA increased only 2-fold for the single I223R mutant and up to 8-fold for the double mutant. Oseltamivir inhibition constants (KI) increased 48-fold in the single I223R mutant and 7500-fold in the double mutant. In both cases the change was largely accounted for by an increased dissociation rate constant for oseltamivir, but the inhibition constants for zanamivir were less increased. We have used X-ray crystallography to better understand the effect of mutation I223R on drug binding. We find that there is shrinkage of a hydrophobic pocket in the active site as a result of the I223R change. Furthermore, R223 interacts with S247 which changes the rotamer it adopts and, consequently, binding of the pentoxyl substituent of oseltamivir is not as favorable as in the wild type. However, the polar glycerol substituent present in zanamivir, which mimics the natural substrate, is accommodated in the I223R mutant structure in a similar way to wild type, thus explaining the kinetic data. Our structural data also show that, in contrast to a recently reported structure, the active site of 2009 pandemic neuraminidase can adopt an open conformation.

Journal Keywords: Amino; Antiviral; Binding; Crystallography; X-Ray; Drug; Viral; Enzyme; Humans; Hydrophobic; Influenza; H1N1; Influenza; Human; Mutation; Neuraminidase; Oseltamivir; Pandemics; Protein; Zanamivir

Diamond Keywords: Swine Flu; Influenza; Viruses; Enzymes

Subject Areas: Biology and Bio-materials, Medicine


Instruments: I02-Macromolecular Crystallography , I03-Macromolecular Crystallography , I04-Macromolecular Crystallography

Added On: 11/01/2013 15:19

Discipline Tags:

Pathogens Infectious Diseases Health & Wellbeing Structural biology Drug Discovery Life Sciences & Biotech

Technical Tags:

Diffraction Macromolecular Crystallography (MX)