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Correlating conformational shift induction with altered inhibitor potency in a multidrug resistant HIV-1 protease variant.

ABSTRACT: Inhibitor-induced conformational ensemble shifts in a multidrug resistant HIV-1 protease variant, MDR769, are characterized by site-directed spin labeling double electron-electron resonance spectroscopy. For MDR769 compared to the native enzyme, changes in inhibitor IC(50) values are related to a parameter defined as |?C|, which is the relative change in the inhibitor-induced shift to the closed state. Specifically, a linear correlation is found between |?C| and the magnitude of the change in IC(50), provided that inhibitor binding is not too weak. Moreover, inhibitors that exhibit MDR769 resistance no longer induce a strong shift to a closed conformational ensemble as seen previously in the native enzyme.

SUBMITTER: de Vera IM

PROVIDER: S-EPMC4768727 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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Correlating conformational shift induction with altered inhibitor potency in a multidrug resistant HIV-1 protease variant.

de Vera Ian Mitchelle S IM Blackburn Mandy E ME Fanucci Gail E GE

Biochemistry 20120928 40

Inhibitor-induced conformational ensemble shifts in a multidrug resistant HIV-1 protease variant, MDR769, are characterized by site-directed spin labeling double electron-electron resonance spectroscopy. For MDR769 compared to the native enzyme, changes in inhibitor IC(50) values are related to a parameter defined as |ΔC|, which is the relative change in the inhibitor-induced shift to the closed state. Specifically, a linear correlation is found between |ΔC| and the magnitude of the change in IC ...[more]

PMID: 23009326

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