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Biochemistry, Biophysics, and Structural Biology Commons

Open Access. Powered by Scholars. Published by Universities.®

Microbiology

Celia A. Schiffer

Sulfonamides

Publication Year

Articles 1 - 3 of 3

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Structural And Thermodynamic Basis Of Amprenavir/Darunavir And Atazanavir Resistance In Hiv-1 Protease With Mutations At Residue 50, Seema Mittal, Rajintha Bandaranayake, Nancy King, Moses Prabu-Jeyabalan, Madhavi Nalam, Ellen Nalivaika, Nese Yilmaz, Celia Schiffer Jul 2013

Structural And Thermodynamic Basis Of Amprenavir/Darunavir And Atazanavir Resistance In Hiv-1 Protease With Mutations At Residue 50, Seema Mittal, Rajintha Bandaranayake, Nancy King, Moses Prabu-Jeyabalan, Madhavi Nalam, Ellen Nalivaika, Nese Yilmaz, Celia Schiffer

Celia A. Schiffer

Drug resistance occurs through a series of subtle changes that maintain substrate recognition but no longer permit inhibitor binding. In HIV-1 protease, mutations at I50 are associated with such subtle changes that confer differential resistance to specific inhibitors. Residue I50 is located at the protease flap tips, closing the active site upon ligand binding. Under selective drug pressure, I50V/L substitutions emerge in patients, compromising drug susceptibility and leading to treatment failure. The I50V substitution is often associated with amprenavir (APV) and darunavir (DRV) resistance, while the I50L substitution is observed in patients failing atazanavir (ATV) therapy. To explain how APV, …


Decomposing The Energetic Impact Of Drug Resistant Mutations In Hiv-1 Protease On Binding Drv, Yufeng Cai, Celia Schiffer Nov 2011

Decomposing The Energetic Impact Of Drug Resistant Mutations In Hiv-1 Protease On Binding Drv, Yufeng Cai, Celia Schiffer

Celia A. Schiffer

Darunavir (DRV) is a high affinity (4.5x10(-12) M, DeltaG = -15.2 kcal/mol) HIV-1 protease inhibitor. Two drug-resistant protease variants FLAP+ (L10I, G48V, I54V, V82A) and ACT (V82T, I84V) decrease the binding affinity with DRV by 1.0 kcal/mol and 1.6 kcal/mol respectively. In this study the absolute and relative binding free energies of DRV with wild-type protease, FLAP+ and ACT were calculated with MM-PB/GBSA and thermodynamic integration methods, respectively. Free energy decomposition elucidated that the mutations conferred resistance by distorting the active site of HIV-1 protease so that the residues that lost binding free energy were not limited to the sites …


The Effect Of Clade-Specific Sequence Polymorphisms On Hiv-1 Protease Activity And Inhibitor Resistance Pathways, Rajintha Bandaranayake, Madhavi Kolli, Nancy King, Ellen Nalivaika, Annie Heroux, Junko Kakizawa, Wataru Sugiura, Celia Schiffer Nov 2011

The Effect Of Clade-Specific Sequence Polymorphisms On Hiv-1 Protease Activity And Inhibitor Resistance Pathways, Rajintha Bandaranayake, Madhavi Kolli, Nancy King, Ellen Nalivaika, Annie Heroux, Junko Kakizawa, Wataru Sugiura, Celia Schiffer

Celia A. Schiffer

The majority of HIV-1 infections around the world result from non-B clade HIV-1 strains. The CRF01_AE (AE) strain is seen principally in Southeast Asia. AE protease differs by approximately 10% in amino acid sequence from clade B protease and carries several naturally occurring polymorphisms that are associated with drug resistance in clade B. AE protease has been observed to develop resistance through a nonactive-site N88S mutation in response to nelfinavir (NFV) therapy, whereas clade B protease develops both the active-site mutation D30N and the nonactive-site mutation N88D. Structural and biochemical studies were carried out with wild-type and NFV-resistant clade B …