Inhibitor-induced conformational shifts and ligand-exchange dynamics for HIV-1 protease measured by pulsed EPR and NMR spectroscopy.
J Phys Chem B
; 116(49): 14235-44, 2012 Dec 13.
Article
em En
| MEDLINE
| ID: mdl-23167829
ABSTRACT
Double electron-electron resonance (DEER) spectroscopy was utilized to investigate shifts in conformational sampling induced by nine FDA-approved protease inhibitors (PIs) and a nonhydrolyzable substrate mimic for human immunodeficiency virus type 1 protease (HIV-1 PR) subtype B, subtype C, and CRF_01 A/E. The ligand-bound subtype C protease has broader DEER distance profiles, but trends for inhibitor-induced conformational shifts are comparable to those previously reported for subtype B. Ritonavir, one of the strong-binding inhibitors for subtypes B and C, induces less of the closed conformation in CRF_01 A/E. (1)H-(15)N heteronuclear single-quantum coherence (HSQC) spectra were acquired for each protease construct titrated with the same set of inhibitors. NMR (1)H-(15)N HSQC titration data show that inhibitor residence time in the protein binding pocket, inferred from resonance exchange broadening, shifting or splitting correlates with the degree of ligand-induced flap closure measured by DEER spectroscopy. These parallel results show that the ligand-induced conformational shifts resulting from protein-ligand interactions characterized by DEER spectroscopy of HIV-1 PR obtained at the cryogenic temperature are consistent with more physiological solution protein-ligand interactions observed by solution NMR spectroscopy.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Termodinâmica
/
Protease de HIV
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Inibidores da Protease de HIV
Idioma:
En
Revista:
J Phys Chem B
Ano de publicação:
2012
Tipo de documento:
Article