Limits...
Aminoadamantanes with persistent in vitro efficacy against H1N1 (2009) influenza A.

Kolocouris A, Tzitzoglaki C, Johnson FB, Zell R, Wright AK, Cross TA, Tietjen I, Fedida D, Busath DD - J. Med. Chem. (2014)

Bottom Line: The addition of as little as one CH2 group to the methyl adduct of the amantadine/rimantadine analogue, 2-methyl-2-aminoadamantane, led to activity in vitro against two M2 S31N viruses A/Calif/07/2009 (H1N1) and A/PR/8/34 (H1N1) but not to a third A/WS/33 (H1N1).Solid state NMR of the transmembrane domain (TMD) with a site mutation corresponding to S31N shows evidence of drug binding.The observations of an HA1 mutation, N160D, near the sialic acid binding site in both 6-resistant A/Calif/07/2009(H1N1) and the broadly resistant A/WS/33(H1N1) and of an HA1 mutation, I325S, in the 6-resistant virus at a cell-culture stable site suggest that the drugs tested here may block infection by direct binding near these critical sites for virus entry to the host cell.

View Article: PubMed Central - PubMed

Affiliation: Department of Pharmaceutical Chemistry, Faculty of Pharmacy, National and Kapodistrian University of Athens , Athens 15771, Greece.

ABSTRACT
A series of 2-adamantanamines with alkyl adducts of various lengths were examined for efficacy against strains of influenza A including those having an S31N mutation in M2 proton channel that confer resistance to amantadine and rimantadine. The addition of as little as one CH2 group to the methyl adduct of the amantadine/rimantadine analogue, 2-methyl-2-aminoadamantane, led to activity in vitro against two M2 S31N viruses A/Calif/07/2009 (H1N1) and A/PR/8/34 (H1N1) but not to a third A/WS/33 (H1N1). Solid state NMR of the transmembrane domain (TMD) with a site mutation corresponding to S31N shows evidence of drug binding. But electrophysiology using the full length S31N M2 protein in HEK cells showed no blockade. A wild type strain, A/Hong Kong/1/68 (H3N2) developed resistance to representative drugs within one passage with mutations in M2 TMD, but A/Calif/07/2009 S31N was slow (>8 passages) to develop resistance in vitro, and the resistant virus had no mutations in M2 TMD. The results indicate that 2-alkyl-2-aminoadamantane derivatives with sufficient adducts can persistently block p2009 influenza A in vitro through an alternative mechanism. The observations of an HA1 mutation, N160D, near the sialic acid binding site in both 6-resistant A/Calif/07/2009(H1N1) and the broadly resistant A/WS/33(H1N1) and of an HA1 mutation, I325S, in the 6-resistant virus at a cell-culture stable site suggest that the drugs tested here may block infection by direct binding near these critical sites for virus entry to the host cell.

Show MeSH

Related in: MedlinePlus

Superimposed PISEMA spectra of the S31NM2 transmembrane domain(residues 22–46), 15N labeled at residues V28, A30,and I42, in dimyristoylphosphatidylcholine bilayers uniformly alignedon glass slides with (red) and without (black) compound 6. Assignments were made based on the known structure and spectraof WT M2 TMD.15 The assignments with drugfollow based on the rotational orientation of the helices.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4127532&req=5

fig1: Superimposed PISEMA spectra of the S31NM2 transmembrane domain(residues 22–46), 15N labeled at residues V28, A30,and I42, in dimyristoylphosphatidylcholine bilayers uniformly alignedon glass slides with (red) and without (black) compound 6. Assignments were made based on the known structure and spectraof WT M2 TMD.15 The assignments with drugfollow based on the rotational orientation of the helices.

Mentions: PISA wheel analysisgives a direct readout of helix tilt relative to the membrane normalfor membrane proteins in uniformly oriented lipid bilayer preparationsfrom solid state NMR PISEMA experiments.1315N anisotropic chemical shifts and 15N–1H dipolar interactions observed in these spectra are verysensitive to the orientation of the peptide planes relative to thebilayer normal. Binding of compound 6 shifts the signalsfor three pertinent backbone amides that were isotopically labeled(Figure 1).


Aminoadamantanes with persistent in vitro efficacy against H1N1 (2009) influenza A.

Kolocouris A, Tzitzoglaki C, Johnson FB, Zell R, Wright AK, Cross TA, Tietjen I, Fedida D, Busath DD - J. Med. Chem. (2014)

Superimposed PISEMA spectra of the S31NM2 transmembrane domain(residues 22–46), 15N labeled at residues V28, A30,and I42, in dimyristoylphosphatidylcholine bilayers uniformly alignedon glass slides with (red) and without (black) compound 6. Assignments were made based on the known structure and spectraof WT M2 TMD.15 The assignments with drugfollow based on the rotational orientation of the helices.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4127532&req=5

fig1: Superimposed PISEMA spectra of the S31NM2 transmembrane domain(residues 22–46), 15N labeled at residues V28, A30,and I42, in dimyristoylphosphatidylcholine bilayers uniformly alignedon glass slides with (red) and without (black) compound 6. Assignments were made based on the known structure and spectraof WT M2 TMD.15 The assignments with drugfollow based on the rotational orientation of the helices.
Mentions: PISA wheel analysisgives a direct readout of helix tilt relative to the membrane normalfor membrane proteins in uniformly oriented lipid bilayer preparationsfrom solid state NMR PISEMA experiments.1315N anisotropic chemical shifts and 15N–1H dipolar interactions observed in these spectra are verysensitive to the orientation of the peptide planes relative to thebilayer normal. Binding of compound 6 shifts the signalsfor three pertinent backbone amides that were isotopically labeled(Figure 1).

Bottom Line: The addition of as little as one CH2 group to the methyl adduct of the amantadine/rimantadine analogue, 2-methyl-2-aminoadamantane, led to activity in vitro against two M2 S31N viruses A/Calif/07/2009 (H1N1) and A/PR/8/34 (H1N1) but not to a third A/WS/33 (H1N1).Solid state NMR of the transmembrane domain (TMD) with a site mutation corresponding to S31N shows evidence of drug binding.The observations of an HA1 mutation, N160D, near the sialic acid binding site in both 6-resistant A/Calif/07/2009(H1N1) and the broadly resistant A/WS/33(H1N1) and of an HA1 mutation, I325S, in the 6-resistant virus at a cell-culture stable site suggest that the drugs tested here may block infection by direct binding near these critical sites for virus entry to the host cell.

View Article: PubMed Central - PubMed

Affiliation: Department of Pharmaceutical Chemistry, Faculty of Pharmacy, National and Kapodistrian University of Athens , Athens 15771, Greece.

ABSTRACT
A series of 2-adamantanamines with alkyl adducts of various lengths were examined for efficacy against strains of influenza A including those having an S31N mutation in M2 proton channel that confer resistance to amantadine and rimantadine. The addition of as little as one CH2 group to the methyl adduct of the amantadine/rimantadine analogue, 2-methyl-2-aminoadamantane, led to activity in vitro against two M2 S31N viruses A/Calif/07/2009 (H1N1) and A/PR/8/34 (H1N1) but not to a third A/WS/33 (H1N1). Solid state NMR of the transmembrane domain (TMD) with a site mutation corresponding to S31N shows evidence of drug binding. But electrophysiology using the full length S31N M2 protein in HEK cells showed no blockade. A wild type strain, A/Hong Kong/1/68 (H3N2) developed resistance to representative drugs within one passage with mutations in M2 TMD, but A/Calif/07/2009 S31N was slow (>8 passages) to develop resistance in vitro, and the resistant virus had no mutations in M2 TMD. The results indicate that 2-alkyl-2-aminoadamantane derivatives with sufficient adducts can persistently block p2009 influenza A in vitro through an alternative mechanism. The observations of an HA1 mutation, N160D, near the sialic acid binding site in both 6-resistant A/Calif/07/2009(H1N1) and the broadly resistant A/WS/33(H1N1) and of an HA1 mutation, I325S, in the 6-resistant virus at a cell-culture stable site suggest that the drugs tested here may block infection by direct binding near these critical sites for virus entry to the host cell.

Show MeSH
Related in: MedlinePlus